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Calendar of Events 2009<br />
<strong>Smile</strong> <strong>Dental</strong> Journal Volume 4, Issue 1 - 2009<br />
5
Pediatric Dentistry<br />
The Clinical Applications of Tooth Mousse TM and<br />
other CPP-ACP Products in Caries Prevention:<br />
Evidence-Based Recommendations<br />
Dr. Ola B. Al-Batayneh<br />
BDS, MDSc, JDB (Paed),<br />
FRACDS (Paed)<br />
. Assistant Prof. Department<br />
of Preventive Dentistry,<br />
Faculty of Dentistry,<br />
Jordan Univesity of Science<br />
& Technology (JUST)<br />
. Specialist Pediatric Dentistry,<br />
King Abdullah University<br />
Teaching Hospital, Jordan<br />
olabt@hotmail.com<br />
8 <strong>Smile</strong> <strong>Dental</strong> Journal Volume 4, Issue 1 - 2009<br />
Abstract<br />
Casein phosphor-peptides-amorphous calcium phosphate (CPP-ACP) products have been<br />
widely used in the field of preventive dentistry. CPP exerts its main effect through binding<br />
and stabilizing calcium and phosphate ions (ACP) in an amorphous, non-crystalline state<br />
where they can enter enamel and enhance remineralization. The following article presents a<br />
background on these products, in addition to the scientific rationale behind their anti-cariogenic<br />
mechanisms and a great deal of useful evidence-based clinical applications.<br />
Key words: CPP-ACP, Tooth Mousse, Recaldent, remineralization, casein, milk.<br />
Since its introduction in late 2002, GC Tooth Mousse has quickly become a useful topical coating<br />
for teeth with a myriad of uses. More and more applications are being suggested for Tooth<br />
Mousse and so the intent of this article was to compile the most common applications. If you<br />
already use Tooth Mousse, it’s hoped that you may find some additional applications by reading<br />
through the growing body of evidence supporting its clinical effectiveness. If you haven’t<br />
tried this amazing product, you will find lots of encouragement to sample the product.<br />
Casein Phosphopeptides (CPP)<br />
Casein, a bovine milk phosphor-protein is known to interact with calcium and phosphate and<br />
is a natural food component. 1 Its technical name is casein phosphor-peptides-amorphous<br />
calcium phosphate, or CPP-ACP. It was discovered by Prof. Eric Reynolds at the school of<br />
<strong>Dental</strong> Science at the University of Melbourne in Australia. Casein phosphor-peptides (CPP)<br />
are responsible for the high bioavailability of calcium from milk and other dairy products.<br />
CPP have the ability to bind and stabilize calcium and phosphate in solution, as well as to<br />
bind to dental plaque and tooth enamel. Calcium phosphate is normally insoluble, i.e. forms<br />
a crystalline structure at neutral pH. However, the CPP keeps the calcium and phosphate in<br />
an amorphous, non-crystalline state. In this amorphous state, calcium and phosphate ions can<br />
enter the tooth enamel. The high concentration of calcium and phosphate ions in dental plaque<br />
have been extensively researched and proven to reduce the risk of enamel demineralization and<br />
promote remineralization of tooth enamel. 2<br />
Casein phosphor-peptides (CPP) containing the cluster sequence [-Ser(P)-Ser(P)-Ser(P)-Glu-Glu]<br />
have a remarkable ability to stabilize calcium phosphate in solution and substantially increase<br />
the level of calcium phosphate in dental plaque. 3<br />
Reynolds and coworkers, in a series of publications (reviewed in 1999), demonstrated the<br />
role of casein in the anti-cariogenic and the enamel-protective effects of milk. 4 Calcium and<br />
phosphate bound to the protein became available under the acid conditions of the plaque<br />
and reduced demineralization. The investigators isolated casein phospho-peptides from milk<br />
that react with high concentrations of calcium and phosphate to form colloidal amorphous<br />
calcium phosphate complexes (CPP-ACP). 4<br />
The CPP-ACP products contain no lactose which is the carbohydrate in milk that can cause<br />
gastrointestinal upset sometimes seen with dairy-based products. Therefore, despite its dairy<br />
origin, gastrointestinal symptoms are not seen with CPP-ACP. However, patients with a known<br />
allergy to milk protein should avoid products containing CPP-ACP because they will be allergic<br />
to the casein protein from which CPP-ACP is derived. 2<br />
Background<br />
Dairy products (milk, milk concentrates, and cheeses) have been shown to be anti-cariogenic<br />
in animal and human in situ caries models. This effect could not be attributed to a change in<br />
level of infection of Streptococcus sobrinus and so was attributed to a direct chemical effect
y cheese components. It has been concluded from many<br />
studies that the protective effect was best attributed to the<br />
phospho-protein casein and calcium phosphate contents of<br />
the cheese. 5,6<br />
Milk is known to be harmful in baby bottle tooth decay.<br />
A condition also termed early childhood caries in which<br />
infants develop rampant tooth decay when they are left to<br />
fall asleep with a bottle of milk, juice or any drink containing<br />
fermentable carbohydrates. Milk pools in the infant’s mouth<br />
over a prolonged time and plaque microorganisms cotinually<br />
ferment the milk lactose. The result is an almost continuous<br />
exposure to acids where plaque accumulates on the teeth<br />
and a progressive dissolution of the tooth enamel under the<br />
plaque occurs. 7<br />
Milk has been shown to be essentially “tooth friendly”<br />
(i.e. its consumption does not increase plaque acidity or<br />
conversely, lower pH) in human trials. Kashket and Yaskell in<br />
1997, using an intraoral caries test system in human<br />
volunteers, demonstrated that enamel demineralization<br />
was reduced by approximately 50% when 3% calcium<br />
lactate was added in the preparation of cookies made with<br />
flour, shortening, and water. 7<br />
Investigators have concluded that milk by itself was not<br />
cariogenic. 8 Some anticariogenic characteristics of milk may<br />
be summarized in the following points:<br />
1. Milk produced only a minimal drop in plaque pH in<br />
subjects who rinsed with milk for 30 seconds after refraining<br />
from tooth brushing for three days, the extent and duration<br />
of which was recognized as non-cariogenic. 9<br />
2. Milk greatly reduced the dissolution of enamel when<br />
extracted teeth were incubated for 24 hours in either<br />
acidified buffers or in saliva. 9<br />
3. Calcium and phosphates in the milk were in large part<br />
responsible for the observed enamel-protective effects. 10<br />
4. The casein products of milk were rapidly absorbed onto<br />
the enamel surfaces and provided resistance to the acid.<br />
Milk itself brought about little enamel demineralization. 11<br />
Supplementation of a normal diet with milk substantially<br />
reduced caries in rats. 8<br />
5. The k-casein fractions in milk can modulate adherence<br />
of a strain of the cariogenic microorganism, Streptococcus<br />
mutans, to hydroxy-apatite. Adherence of Streptococci to<br />
enamel is an important element in the formation of dental<br />
plaque. 12<br />
6. Micellar casein, a dietary component in milk, selectively<br />
modifies the microbial composition of dental plaque,<br />
reducing its cariogenic potential. The Guggenheim et al.<br />
study in 1999 was the first study that demonstrated the<br />
dietary component- micellar casein- that selectively<br />
modifies the microbial composition of dental plaque,<br />
reducing its cariogenic potential. 13<br />
Enamel protective effects of cheese have been studied<br />
and measurements of plaque pH in humans have shown<br />
that cheese consumption does not lead to decreased pH.<br />
Instead, Rugg-Gunn et al., in 1975 found that chewing<br />
cheddar cheese after consumption of sugary food, rapidly<br />
returned the plaque pH towards neutrality. 14 A number of<br />
investigators have proposed various mechanisms to explain<br />
the observed anti-cariogenic effects of cheeses (Table 1). 7
Pediatric Dentistry<br />
Table 1. Anti-cariogenic effects of cheese.<br />
Evidence-Based Anticariogenic Mechanism of CPP-ACP<br />
The anti-cariogenic mechanism of CPP-ACP is achieved by<br />
the incorporation of the nano-complexes of the amorphous<br />
calcium phosphate (ACP) into plaque and onto the tooth<br />
surface. The casein phosphor-peptides (CPP) have an<br />
important role as an ACP carrier localizing the highly solble<br />
calcium phosphate phase at the tooth surface. This localization<br />
maintains high concentration gradients of calcium and<br />
phosphate ions in the subsurface enamel, thereby facilitating<br />
remineralization. 4<br />
Casein phosphopeptide calcium-phosphate complexes<br />
(CPP-CP) have been found to increase the levels of calcium<br />
and phosphate in plaque up to five folds in humans in in<br />
situ caries models and short-term mouthwash studies. 15 The<br />
proposed mechanism of their anticariogenicity is that they<br />
act as a calcium-phosphate reservoir, buffering the activities<br />
of free calcium and phosphate ions in the plaque fluid helping<br />
to maintain a state of supersaturation with respect to enamel<br />
minerals, thereby depressing enamel demineralization and<br />
enhancing remineralization. 16 The binding of ACP to CPP is<br />
pH dependent; with binding decreasing as the pH falls.<br />
Casein phosphopeptide-amorphous calcium phosphate<br />
compounds (CPP-ACP) have been demonstrated to have<br />
anticariogenic potential in laboratory, animal, and human in<br />
situ experiments. 3-5,17-18<br />
Rose (2000a) study investigated these effects by measuring<br />
the affinity and capacity of Streptococcus mutans for CPP-ACP.<br />
The study demonstrated that CPP-ACP binds with about<br />
twice the affinity of the bacterial cells for calcium. Application<br />
of CPP-ACP to plaque may cause a transient rise in plaque<br />
fluid free calcium which may assist remineralization.<br />
Subsequently, CPP-ACP will form a source of readily available<br />
calcium to inhibit demineralization. 18<br />
Rose (2000b) investigated the effects of casein phospho-peptides<br />
(CPP) in reducing demineralization and enhancing reineralization<br />
in tooth enamel by measuring the effect of CPP-ACP on<br />
calcium diffusion in plaque. 19 Calcium diffusion was measured<br />
in streptococcal model plaques. This demonstrated that by<br />
providing a large number of possible binding sites for calcium,<br />
0.1% CPP-ACP reduces the calcium diffusion coefficient by<br />
about 65% at pH 7 and 35% at pH 5. Hence, CPP-ACP binds<br />
well to plaque, providing a large calcium reservoir within<br />
the plaque and slowing diffusion of free calcium. This is<br />
likely to restrict mineral loss during a cariogenic episode<br />
and provide a potential source of calcium for subsequent<br />
remineralization. 19<br />
CPP-ACP has been shown in animal studies to enhance the<br />
10 <strong>Smile</strong> <strong>Dental</strong> Journal Volume 4, Issue 1 - 2009<br />
effects of fluoride. Animals receiving 0.5% CPP-ACP and 500<br />
ppm fluoride had significantly lower caries activity than<br />
those animals receiving either CPP-ACP or fluoride alone.<br />
This is actually not surprising, since fluoride requires a good<br />
source of calcium and phosphate for remineralization of<br />
tooth enamel with the more acid-resistant fluorapatite, and<br />
CPP-ACP provides this in an amorphous, soluble form. 2,17<br />
In a human in situ enamel demineralization study, a 1.0%<br />
w/v CPP-ACP solution used twice daily, produced a 51±19%<br />
reduction in enamel mineral loss caused by frequent sugar<br />
solution exposure. 3 The twice daily use of the 1.0% CPP-ACP<br />
solution resulted in a 144% increase in calcium level and a<br />
160% increase in inorganic phosphate level. 3 These results<br />
suggested that an anticariogenic mechanism for the CPP-ACP<br />
exists, where the CPP stabilizes and localizes ACP at the<br />
tooth surface, thereby buffering plaque pH, depressing<br />
enamel demineralization and enhancing remineralization. 3<br />
These results were extended by the incorporation of<br />
CPP-ACP into sugar-free chewing gum and in situ clinical<br />
studies demonstrated that the addition of 1.0% CPP-ACP to<br />
either sorbitol or xylitol-based gym resulted in an increase<br />
in enamel remineralization of 100% relative to the control<br />
gum. 20 Shen and Reynolds in 2001, in an in situ human<br />
study showed that CPP-ACP in a sugar-free chewing gum<br />
enhanced remineralization of enamel subsurface lesions in<br />
situ by 100-150%, when compared with the control sugar-free<br />
gum not containing CPP-ACP. 21 The results revealed a doserelated<br />
increase in enamel remineralization independent of<br />
chewing gum weight and type.<br />
Reynolds in 2003 performed a clinical study that compared<br />
the ability of CPP-ACP with that of other forms of calcium,<br />
to be retained in supragingival plaque and remineraize<br />
enamel subsurface lesions in situ when delivered in a<br />
mouthrinse or sugar-free gum. 22 CPP inhibited the tranformation<br />
of amorphous calcium phosphate (ACP) into the crystalline<br />
phases, such that they did not directly promote calculus<br />
formation like other plaque mineralizing solutions. The<br />
study indicated that the CPP-ACP was superior to that<br />
achieved with other forms of calcium in remineralizing<br />
enamel susurface lesions. 22<br />
A recent study by Kumar in 2008 has proved great efficiency<br />
of CPP-ACP in remineralization of initial enamel lesions and<br />
showed a higher remineralizing potential when applied as<br />
a topical coating after the use of a topical toothpaste (1100<br />
ppm), than when used alone. 23 Since additive effects were<br />
obtained when CPP-ACP is used in conjunction with fluoride,
it can be recommended that CPP-ACP should be used as<br />
a self-applied topical coating after the teeth have been<br />
brushed with a fluoridated toothpaste by children who<br />
have a high caries risk. 23<br />
Interaction of CPP-ACP with Fluoride<br />
The CPP-ACP and fluoride have been shown to have additive<br />
effects in reducing caries experience. The additive anticariogenic<br />
effect of the 1.0% CPP-ACP and 500ppm fluoride in the rat<br />
caries experiments led to the investigation of the potential<br />
interaction between the CPP-ACP and fluoride. 17 The fluoride<br />
ion had incorporated into the ACP phase that was stabilized<br />
by the CPP to produce a novel amorphous calcium fluoride<br />
phosphate phase (ACFP) at the tooth surface. The identification<br />
of this novel amorphous calcium fluoride phosphate (ACFP)<br />
phase led to the proposition that the formation of this phase<br />
is responsible for the observed additive anticariogenic effect<br />
of CPP-ACP and fluoride. 17<br />
The formation of fluoroapatite, calcium and phosphate<br />
ions must be co-localized in plaque at the tooth surface<br />
with the fluoride ion for promoting enamel remineralization.<br />
Therefore the additive anti-cariogenic effect of CPP-ACP and<br />
fluoride may be attributable to the localization of ACFP at the<br />
tooth surface by the CPP, which would co-localize calcium,<br />
phosphate and fluoride. CPP may be an excellent delivery<br />
vehicle for the co-localization of calcium, phosphate, and<br />
fluoride at the tooth surface in a slow release amorphous<br />
form with superior clinical efficacy. 3<br />
Mazzaoui et al. in 2003 evaluated the effect of incorporating<br />
CPP-ACP into a self-cured glass ionomer cement (GIC) in order<br />
to enhance its anticariogenic potential. 24 Incorporation of<br />
1.56% w/w CPP-ACP into the GIC significantly increased<br />
microtensile bond strength to dentin by 33%, increased its<br />
compressive strength by 23% and significantly enhanced<br />
the release of calcium, phosphate, and fluoride ions at neutral<br />
and acidic pH. The release of CPP-ACP and fluoride from<br />
the CCP-ACP-containing GIC as the acid erodes the cement<br />
was associated with enhanced protection of the adjacent<br />
dentin during acid challenge in vitro. It was concluded that<br />
the 1.56%-CPP-ACP-containing GIC might be a superior<br />
restorative/base with an improved anticariogenic potential. 24<br />
Furthermore, CPP has been shown to keep calcium, phosphate<br />
and fluoride as ions in solution, thereby enhancing the efficacy<br />
of the fluoride as a remineralizing agent. 2<br />
CPP-ACP has been incorporated into commercial products<br />
by (GC corporation, Tokyo, Japan) such as:<br />
1. GC Tooth Mousse (water based, sugar free crème with<br />
various flavors available).<br />
2. GC MI Paste Plus (with the incorporation of 900 ppm fluoride).<br />
3. Recaldent Chewing Gum (xylitol and CPP-ACP).<br />
4. Recaldent Lozenges.<br />
Clinical Applications of CPP-ACP<br />
The applications of CPP-ACP include 25 ;<br />
- Used for both primary and permanent teeth. Fluoride-free<br />
regular Tooth Mousse is a safe product to use in babies’<br />
teeth especially young children under 2 years of age with early<br />
childhood caries.<br />
- Used for patients with special needs such as those with<br />
intellectual impairment, developmental and physical disabilities,<br />
cerebral palsy, Down syndrome and those with any medical
Pediatric Dentistry<br />
problems such as those undergoing radiation therapy.<br />
- Used for high caries-risk patients in an attempt to remineralize<br />
early enamel lesions, early childhood caries, stabilize carious<br />
lesions awaiting treatment and root surface caries.<br />
- Used in cases of molar incisor hypomineralization (MIH).<br />
This is done for remineralizing hypoplastic molars and<br />
remineralization of white spot lesions (enamel opacities and<br />
some cases of mild fluorosis).<br />
- Used in cases of erosion whereby it neutralizes acid challenges<br />
from internal and external acid sources. 26<br />
- Used in the prevention of tooth wear.<br />
- Used in patients with orthodontic appliances for the purpose<br />
of caries prevention and prevention/remineralization of<br />
white spot lesions.<br />
- Used to reduce dentinal sensitivity by occluding patent tubules.<br />
- Used as a substitute for toothpaste in those allergic to<br />
commercial toothpastes.<br />
Instructions for Clinicians on the Use of Tooth Mousse (TM)<br />
1. Explain the following product characteristics to the patients/<br />
child’s parent:<br />
- Tooth mousse is commercially available through dentists only.<br />
- The active ingredient is derived from cow’s milk, and<br />
therefore cannot be used for patients with allergies to<br />
cow’s milk (milk protein allergy), but can however be used<br />
for patients complaining of lactose intolerance since no<br />
lactose is present in Tooth Mousse. Besides, patients who<br />
have an allergy to benzoates or some other components<br />
shouldn’t use the product.<br />
- The product has been extensively tested; very safe with<br />
minimal side effects, if any. It has been classified by the<br />
United States Food and Drug Administration as GRAS (generally<br />
recognized as safe). Any material that is swallowed is safe<br />
as it will contribute to dietary calcium. It can be used with<br />
patients of any age.<br />
- The product is highly effective for re-mineralization of<br />
enamel and works well with fluoride.<br />
- The product has a pleasant taste and comes with different flavors.<br />
2. Explain benefits of TM for enamel hypoplasia, cases of<br />
erosion, caries prevention...etc.<br />
3. Explain the proper way of using TM;<br />
- It should be rubbed on tooth surfaces after brushing<br />
and no rinsing should be done after that.<br />
- It should be used twice daily; after morning toothbrushing<br />
and before going to bed, avoiding eating or drinking for<br />
30 minutes afterwards.<br />
4. Obtain parents’ consent before using the product in children;<br />
- Explain the need to evaluate the product to determine<br />
the effects on your patient for long term use.<br />
- Explain the need to contact the dentist if any problem arises.<br />
5. Evaluate product use; review the patient at 1, 3, 6 and 12<br />
months. File in case notes in patient’s chart.<br />
Conclusions<br />
Based on the previous literature and the proven efficacy of<br />
CPP-ACP products through clinical and laboratory studies,<br />
it seems that we should shift our ways of caries prevention<br />
to include products such as CPP-ACP in our prevention<br />
schemes for patients through remineralization of enamel<br />
and application of minimal invasive approaches in dentistry.<br />
Recent studies support the use of fluoride in toothpastes<br />
and gels with CPP-ACP. CPP-ACP products are recommended<br />
12 <strong>Smile</strong> <strong>Dental</strong> Journal Volume 4, Issue 1 - 2009<br />
to be used twice daily and are safe to be used in young<br />
children. Their use seems to be rewarding in the field of<br />
preventive dentistry.<br />
References<br />
1. Reeves R, Latour N. Calcium phosphate sequestering phosphopeptide<br />
form casein. Science 1958 Aug;128: 472.<br />
2. Walsh LJ. Preventive Dentistry for the general dental practitioner. Aust<br />
Dent J. 2000 Jun;45(2):76-82.<br />
3. Reynolds EC. Anticariogenic complexes of amorphous calcium<br />
phosphate stabilized by casein phosphopeptides: a review. Spec Care<br />
Dentist. 1998 Jan-Feb;18(1):8-16.<br />
4. Reynolds EC. The role of phosphopeptides in caries prevention. <strong>Dental</strong><br />
Perspectives 1999;3:6-7.<br />
5. Reynolds EC. Remineralization of enamel subsurface lesions by casein<br />
phosphopeptide-stabilized calcium phosphate solutions. J Dent Res.<br />
1997 Sep;76(9):1587-95.<br />
6. Scholz-Ahrens KE, Schrezenmeir J. Effects of bioactive substances in<br />
milk on mineral and trace element metabolism with special reference to<br />
casein phosphopeptides. Br J Nutr. 2000 Nov;84 Suppl 1,S147-53.<br />
7. Kashket S, Yaskell T. Effectiveness of calcium lactate added to food in reducing<br />
intraoral demineralization of enamel. Caries Res. 1997;31(6):429-33.<br />
8. Reynolds Ec, Johnson IH. Effect of milk on caries incidence and bacterial<br />
composition of dental plaque in the rat. Arch Oral Biol. 1981;26(5):445-51.<br />
9. Jenkins GN, Ferguson DB. Milk and dental caries. Br Dent J. 1966 May<br />
17;120(10):472-7.<br />
10. Weiss ME, Bibby BG. Effects of milk on enamel solubility. Arch Oral Biol.<br />
1966 Jan;11(1):49-57.<br />
11. Bibby BG, Huang CT, Zero D, Mundorff SA, Little MF. Protective effect of<br />
milk against in vitro caries. J Dent Res. 1980 Oct;59(10):1565-70.<br />
12. Vacca-Smith AM, Van Wuyckhuyse BC, Tabak LA, Bowen WH. The effect<br />
of milk and casein proteins on the adherence of Streptococcus mutans<br />
to saliva-coated hydroxyapatite. Arch Oral Biol. 1994 Dec;39(12):1063-9.<br />
13. Guggenheim B, Schmid R, Aeschlimann JM, Berrocal R, Neeser JR. Powdered<br />
milk micellar casein prevents oral colonization by Streptococcus sobrinus<br />
and dental caries in rats: A basis for the caries protective effect of dairy<br />
products. Caries Res. 1999 Nov-Dec;33(6):446-54.<br />
14. Rugg-Gunn AJ, Edgar WM, Geddes DA, Jenkins GN. The effect of different<br />
meal patterns upon plaque pH in human subjects. Br Dent J. 1975 Nov<br />
4;139(9):351-6.<br />
15. Reynolds EC. The prevention of sub-surface demineralization of bovine<br />
enamel and change in plaque composition by casein in an intra-oral<br />
model. J Dent Res. 1987 Jun;66(6):1120-7.<br />
16. Reynolds EC. Remineralization of enamel subsurface lesions by casein<br />
phosphopeptide-stabilized calcium phosphate solutions. J Dent Res.<br />
1997 Sep;76(9):1587-95.<br />
17. Reynolds EC, Cain CJ, Webber FL, Black CL, Riley PF, Johnson IH, et al.<br />
Anticariogenicity of calcium phosphate complexes of tryptic casein<br />
phosphopeptides in the rat. J Dent Res. 1995 Jun;74(6):1272-9.<br />
18. Rose RK. Effects of an anticariogenic casein phosphopeptide on<br />
calcium diffusion in streptococcal model dental plaques. Arch Oral Biol.<br />
2000 Jul;45(7):569-75.<br />
19. Rose RK. Binding characteristics of streptococcus mutans for calcium<br />
and casein phosphopeptide. Caries Res. 2000 Sep-Oct;34(5):427-31.<br />
20. Reynolds EC, Black CL, Cai F, Cross KJ, Eakins D, Huq NL, et al. Advances<br />
in enamel remineralization: casein phosphopeptide amorphous calcium<br />
phosphate. J Clin Dent. 1999;10:86-88.<br />
21. Shen P, Cai F, Nowicki A, Vincent J, Reynolds EC. Remineralization of<br />
enamel subsurface lesions by sugar-free chewing gum containing casein<br />
phosphopeptide-amorphous calcium phosphate. J Dent Res. 2001<br />
Dec;80(12):2066-70.<br />
22. Reynolds EC, Cai F, Shen P, Walker GD. Retention in plaque and remineralization<br />
of enamel lesions by various forms of calcium in a mouthrinse or sugar-free<br />
chewing gum. J Dent Res. 2003 Mar;82(3):206-11.<br />
23. Kumar VL, Itthagarun A, King NM. The effect of casein phosphopeptideamorphous<br />
calcium phosphate on remineralization of artificial caries-like<br />
lesions: an in vitro study. Aust Dent J. 2008 Mar;53(1):34-40.<br />
24. Mazzaoui SA, Burrow MF, Tyas MJ, Dashper SG, Eakins D, Reynolds EC.<br />
Incorporation of casein phosphopeptide-amorphous calcium phosphate<br />
into a glass-ionomer cement. J Dent Res. 2003 Nov;82(11):914-8.<br />
25. Walsh L. MI paste, MI paste plus. Anthology of applications. Available<br />
at: URL:http://www.gcamerica.com/products/hp/MIPaste/mipaste_<br />
cookbook.pdf. Accessed 10th Feb 2009.<br />
26. Piekarz C, Ranjitkar S, Hunt D, McIntyre J. An in vitro assessment of the<br />
role of Tooth Mousse in preventing wine erosion. Aust Dent J. 2008<br />
Mar;53(1):22-5.
Endodontics<br />
Proven Strategies to Improve Endodontic Success<br />
and Promote Natural Tooth Retention<br />
Dr. Richard E. Mounce<br />
DDS<br />
. International lecturer in<br />
endodontics<br />
. Private practice Vancouver,<br />
WA, USA<br />
Lineker@comcast.net<br />
16 <strong>Smile</strong> <strong>Dental</strong> Journal Volume 4, Issue 1 - 2009<br />
Abstract<br />
A series of clinically relevant steps to enhance the clinical success of endodontic therapy is<br />
presented. Emphasis has been placed on use of the surgical operating microscope, straight<br />
line access, patency, copious irrigation, frequent recapitulation, passive rotary nickel titanium<br />
file use, bonded obturation and placement of an early coronal seal.<br />
Key words: Root canal, treatment planning, patency, straight-line access, recapitulation,<br />
bonded obturation.<br />
While materials and methods to clean shape and fill the root canal space might differ, the<br />
principles required do not. The goal of endodontic therapy is the three dimensional cleaning,<br />
shaping and obturation of the canal space from the orifice to the minor constriction (MC) of<br />
the apical foramen. Coincident and vitally important to the long-term success of endodontic<br />
treatment is the placement of a coronal seal and a final restoration to provide function and<br />
esthetics. 1-4<br />
To achieve this goal, all mechanical shaping procedures must follow the same principle driven<br />
criterion. These criterion include:<br />
• Keeping the MC at its original position and at its original size.<br />
• Keeping the canal in its original orientation and position within the root.<br />
• Making the final prepared shape to resemble a tapering funnel, with a taper that is continuous<br />
along all levels of the root.<br />
• Preparing the canal to a biologically relevant master apical file (MAF) size. This implies that<br />
the clinician will remove dentin circumferentially at the MC.<br />
• Preparing the canal to a biologically relevant master apical taper.<br />
• Both that the MAF and master apical taper (MAT) are a size that facilitates the optimal flow<br />
of irrigants. At the same time, this size should not predispose the roots to either canal transportation<br />
or vertical root fracture.<br />
In the most general sense, files shape the canals but they do not clean canals. While irrigation<br />
as we know it today does not render a canal bacteria free, especially of biofilms, the goal of<br />
irrigation, during and after the shaping of the root canal system, is to kill bacteria, flush debris,<br />
lubricate, clear the smear layer and dissolve pulp tissue in all the areas of the canal that shaping<br />
instruments do not reach to. In concept, this combination of shaping goals and irrigation acts<br />
to clear the pulp space in such a manner as to facilitate apical healing through diminishing<br />
the bacterial load present within the root canal system once the coronal seal is placed.<br />
Several key concepts guide the steps in endodontic therapy. Adherence to these principles<br />
can enhance the long-term prognosis and improve healing and success rates. These concepts<br />
are, to a large degree, independent of the materials used and include:<br />
The Surgical Operating Microscope<br />
Use of the surgical operating microscope (SOM) increases the visual acuity of all stages of the<br />
endodontic treatment process, for example the use of Global Surgical microscope (Global<br />
Surgical, St. Louis MO, USA). The benefits of the SOM cannot be overstated. Most SOMs have<br />
between 3-6 magnification steps that range from approximately 2x-19x magnification power,<br />
some even more. This allows the clinician to move between powers as the case might require.<br />
In essence, in occlusal access, less magnification is needed and lower powers are used. Once<br />
access is made, the actual location of the canal can be easily found at higher powers and<br />
direct the removal of dentin and allow easier negotiation of the canal space throughout the<br />
initial stages of treatment. In clinical terms, this means that; 2 nd mesial-buccal canals can<br />
virtually always be located with the SOM and improve the chances of their negotiation, that<br />
separated (fractured) rotary nickel titanium (RNT) files can usually be removed, that vertical
Endodontics<br />
(Figure 1)<br />
The surgical operating microscope<br />
(Global Surgical, St. Louis, MO, USA).<br />
(Figure 2 a)<br />
Lack of Straight-line access and<br />
improper orifice management. (Image<br />
courtesy of Dr. Arnaldo Castellucci).<br />
(Figure 2 b)<br />
Straight-line access and proper orifice<br />
management. (Image courtesy of Dr.<br />
Arnaldo Castellucci).<br />
(Figure 3)<br />
EndoBender pliers (SybronEndo,<br />
Orange, CA, USA) used to pre curve<br />
hand K files for negotiation.<br />
and furcal floor fractures can be observed easily, amongst<br />
a host of other important clinical information. Besides, tactile<br />
control at all levels of the process is improved. The use of the<br />
SOM is not limited to endodontics, but rather the instrument<br />
has application in a wide variety of clinical situations that<br />
include all phases of general dentistry. Many teeth that<br />
would have had apical surgery in the past can now be<br />
retreated with great precision as the previous technical<br />
18 <strong>Smile</strong> <strong>Dental</strong> Journal Volume 4, Issue 1 - 2009<br />
deficiency can often be addressed, in part, because it can<br />
both be observed and addressed (Fig. 1).<br />
The Straight-line Access<br />
Straight-line access is essential. Compromises in access can<br />
and will lead to deficiencies in apical third cleaning and<br />
shaping. A lack of straight-line access leads to a loss of both<br />
hand and rotary nickel titanium tactile control. Iatrogenic<br />
events are far more likely to occur without straight-line<br />
access as shaping instruments deflect off of the canal walls<br />
they should not touch. Irrigation becomes less effective<br />
as both the access to and the visualization of the orifices is<br />
diminished. Removal of the cervical dentinal triangle (CDT)<br />
is also critical to provide straight-line access. Straight-line<br />
access under the SOM provides the best possible platform to<br />
manage the shaping of the orifice as well as canal enlargement.<br />
Removal of all coronal restorations, including crowns, is<br />
most ideal. Often caries, coronal fractures, unset restoratives<br />
amongst other sources of coronal leakage are hidden under<br />
restorations. It is possible and occurs frequently enough,<br />
that some teeth, which may appear restorable, once all<br />
coronal restorations are removed, are found to be non<br />
restorable, knowledge of which has obvious clinical benefit (Fig. 2).<br />
Patency of the Canals<br />
Patency is highly valued and ideally obtained and maintained<br />
throughout the process of enlargement. The vast majority<br />
of the iatrogenic events that bedevil clinical procedures can<br />
be avoided through the intelligent, copious and proper use<br />
of hand K files. Once an orifice is uncovered, the cervical<br />
dentinal triangle removed and the orifice enlarged, it is<br />
advisable to use small hand K files to assure the clinician<br />
that the canal is open, patent and negotiable. Some canals<br />
will be open and negotiable easily to the minor constriction<br />
(MC) and others will need to be opened with hand K files to<br />
the MC. Before the use of rotary nickel titanium instruments,<br />
all canals should be enlarged to a minimum #15 hand K file<br />
size ideally to the MC. These hand K files should be precurved<br />
to make them match the expected canal curvature. In addition,<br />
hand K files can be trimmed to match the optimal point of<br />
use. For example, if the clinician is having a challenge getting<br />
past 18 mm in a 22 mm root, using a 25 mm hand K file will<br />
not be efficient as a negotiation instrument. The hand K file<br />
in this example will buckle easily and lack function. Little<br />
intentional pressure will be possible in attempting to bypass<br />
a ledge or blockage. The hand K file can be trimmed to a<br />
length that is slightly longer than the ledge or blockage. In<br />
this example, if the clinician were to cut the hand K file to<br />
19 mm, and precurve it as well, many ledges, calcification,<br />
acute curvatures can be bypassed and allow the creation of<br />
patency (Fig. 3).<br />
Once patency is achieved, and the hand K files reach the<br />
position of the MC, the use of a reciprocating handpiece is<br />
highly valuable in efficiently shaping a glide path to make<br />
way for the use of rotary nickel titanium instruments. The<br />
M4 Safety Handpiece (SybronEndo, Orange, CA, USA) can<br />
be used for this function. The M4 is a reciprocating handpiece<br />
with an attachment that fits onto an electric motor with<br />
an E type coupling, such as the TCM III motor (SybronEndo,<br />
Orange, CA, USA). Hand K files are reciprocated at 900 rpm<br />
at the 18:1 setting. Reciprocation provides the movement of
a hand K file 30 degrees clockwise (CW), 30 degrees counter<br />
clockwise (CCW) and/or it may have some other vertical<br />
competent or degree of CW/CCW movement depending on<br />
the brand used. Clinically, once the hand K file can reach<br />
the MC, the file is left in the canal and the clinician’s hands<br />
are taken away. The M4 is attached to the file and the foot<br />
pedal engaged to power the file. The file is moved with a<br />
vertical amplitude (up and down motion) of 1-3 mm and in<br />
15-30 seconds the canal that may have, for example, barely<br />
allowed a #6 hand K file to be inserted, will enlarge the canal to<br />
the size of a #8 hand K file. The #8 hand K file when reciprocated<br />
next will create the size of a #10 hand K file...etc. This early<br />
enlargement of canals with reciprocation is much faster and<br />
predictable than the manual use of hand K files. Once a #15<br />
hand K file can spin freely at the MC, the canal is ready for<br />
rotary nickel titanium files use. The clinician should irrigate<br />
and recapitulate the canal after every use of the M4 as well<br />
after every use of rotary nickel titanium files. Recapitulation<br />
refers to the placement of a hand K file into the canal after<br />
every RNT insertion to verify that the canal is still open and<br />
negotiable. Recapitulation is usually done with either #6 or<br />
a #8 hand file.<br />
It is not advised to take a hand K file, place it in the M4<br />
handpiece and attempt to drive it to the MC in a calcified<br />
canal as ledging will result. In addition, some canal enlargement<br />
systems recommend reciprocation for the entire preparation.<br />
While these systems have their champions; the possibilities<br />
for canal transportation above a #15 hand file in delicate<br />
apical anatomy are substantial.<br />
Irrigation<br />
Irrigation should be copious and continuous throughout<br />
the instrumentation phase of treatment. The use of EDTA<br />
gel for emulsification is advised in the elimination of vital<br />
and necrotic pulp tissue from the chamber during access<br />
procedures, for example File Eze (Ultradent, South Jordan, UT,<br />
USA). Once the chamber is cleared, and orifices are ready to<br />
be entered, the clinician can change to their liquid bactericidal<br />
irrigant. For vital cases, 5.25% sodium hypochlorite (SH) is<br />
the ideal irrigation solution. The use of 2% Chlorhexidine<br />
(CHX) is however ideal for non-vital and retreatment cases.<br />
The difference is related to the tissue dissolving capability<br />
of SH, a quality that is more essential in vital cases. SH which<br />
carries with it potentially severe toxicity if extruded into the<br />
apical tissues. Its use is much less desirable if a perforation<br />
or open apex is present. CHX is relatively non-toxic and in<br />
the endodontic literature relatively equal in efficacy to SH<br />
without the toxicity. CHX also possesses antimicrobial qualities<br />
after it has been removed from the canal. Its drawback,<br />
while being a relative one, is that CHX does not dissolve tissue.<br />
CHX is effective against E. Faecalis, the primary bacteria<br />
found in cases of endodontic failure.<br />
A final irrigation rinse is used; such as SmearClear (SybronEndo,<br />
Orange, CA, USA), a liquid EDTA solution that is used to<br />
clear the smear layer. In every case, irrigants are heated and<br />
ultrasonically activated. This activation takes place with an<br />
ultrasonic file blank (EMS, Dallas Texas, USA), placed into<br />
an Ultrasonic File Holder (SybronEndo, Orange, CA, USA).<br />
The blank and holder are used with a relatively low power<br />
on an ultrasonic unit with the file blank passively moving<br />
vertically for 15-30 seconds per canal without attempting<br />
to touch the walls. After each activation, the solution is<br />
refreshed. Each canal is activated 2-3 times with both the<br />
bactericidal irrigant and the liquid EDTA solution. A final<br />
rinse of distilled water is carried out. After this rinse, the<br />
smear layer has been cleared and the canal is ready for a<br />
bonded obturation. 5-17<br />
Rotary Nickel Titanium Files<br />
Aside from the strategies above, safe and efficient use<br />
of rotary nickel titanium (RNT) files are a prerequisite for<br />
enlarging canals. RNT instruments must be inserted gently<br />
and passively. Irrespective of the brand or canal third being<br />
shaped, RNT files that are inserted with continuing force,<br />
when the canal resists their advancement, loads the files<br />
with excessive torsion and increases exponentially the<br />
possibilities that the instrument may fracture or that it may<br />
transport the canal. Each RNT file insertion should be followed<br />
by irrigation and recapitulation.<br />
Before RNT file preparation, the clinician should evaluate<br />
the root form to determine the ideal master apical taper<br />
(MAT) and have some concept of the optimal master apical<br />
file (MAF). While a modification of the expected MAF and<br />
MAT will be possible, it is vital that the canal be prepared<br />
to an MAF and MAT of an adequate size. Adequate size in<br />
this context implies a size that gives optimal irrigation and<br />
in which SystemB heat pluggers can achieve their desired<br />
length of insertion apically.<br />
RNT that are manufactured by grinding, are usually prepared<br />
to a taper of .06. This limited taper size is a result of the limitations<br />
of ground file technology. The Twisted File (SybronEndo,<br />
Orange, CA, USA) allows the preparation of canals to larger<br />
tapers and does so, safely and efficiently. For large canals<br />
(the palatal canal of an upper molar), a .10 taper Twisted File<br />
(TF) is often appropriate. For more intermediate canals (the<br />
mesial root of a lower molar), a .08 TF is often appropriate. For<br />
small, complex and calcified canals, (lower anterior teeth) a<br />
.06 TF is often appropriate.<br />
TF can often be used in a single file technique and done<br />
so with as few as 2-3 insertions. As a single file technique,<br />
if the given TF will allow passive insertion to the true working<br />
length, it can be taken apically to the MC. With practice,<br />
fewer TF files and insertions are needed to accomplish the<br />
same preparation as the clinician becomes more experienced<br />
with the instruments. TF eliminates the need for<br />
Gates Glidden drills and other orifice openers. It is rotated<br />
in hands at between 500-900 rpm with the torque control<br />
off. Regardless of the RNT system used, there is no value in<br />
pumping the RNT file into the root repeatedly, one insertion is<br />
made to resistance, the file withdrawn, irrigation and<br />
recapitulation ensues and the desired TF is inserted next (Fig. 4).<br />
Warm Obturation<br />
Obturation should ideally be performed warm in order to<br />
move a heat-softened mass of material into all of the<br />
ramifications of the cleared root canal space. While a<br />
number of warmed techniques have been suggested and<br />
proven in the literature, what is more important than the<br />
given technique per sey, is that the canal is three dimensionally<br />
filled with obturating material from the orifice to the MC.<br />
Coincident to this goal is the desire to have a minimum film<br />
thickness of sealer. While a comprehensive discussion of<br />
<strong>Smile</strong> <strong>Dental</strong> Journal Volume 4, Issue 1 - 2009<br />
19
Endodontics<br />
(Figure 4)<br />
The Twisted File<br />
(SybronEndo, Orange, CA,<br />
USA).<br />
(Figure 5)<br />
RealSeal Bonded<br />
Obturation. SEM courtesy<br />
of Dr. Martin Trope.<br />
(Figure 6)<br />
RealSeal One Bonded<br />
Obturators (SybronEndo,<br />
Orange, CA, USA).<br />
(Figure 7)<br />
Maxcem Elite (Kerr,<br />
Orange, CA, USA).<br />
(Figure 8-10)<br />
Clinical cases using the materials and concepts discussed.<br />
20 <strong>Smile</strong> <strong>Dental</strong> Journal Volume 4, Issue 1 - 2009<br />
obturation techniques is beyond the scope of this paper, suffice<br />
it to write that a greater degree of resistance to coronal<br />
leakage can be obtained with bonded obturation than<br />
gutta percha. Gutta percha does not bond to dentin. Gutta<br />
percha does not bond to sealer. Gutta percha requires a<br />
coronal seal to make it function, in that otherwise, if allowed<br />
to challenge gutta percha, in a time dependent fashion,<br />
bacteria will leak along the length of the canal in either the<br />
gap between the gutta percha and the sealer or the sealer<br />
and the canal wall (depending on whether the smear layer<br />
was cleared and a resin based sealer used). 18-25<br />
Due to the limitations of gutta percha, bonded obturation<br />
in the form of RealSeal (SybronEndo, Orange, CA, USA) is<br />
preferred. RealSeal comes in a master cone based and obturator<br />
(carrier) based variety of the product, RealSeal One Bonded<br />
Obturators (SybronEndo, Orange, CA, USA). While the resistance<br />
to leakage is not absolute, bonded obturation in the form of<br />
RealSeal has been shown, in a number of different studies, to be<br />
superior to gutta percha in resistance of coronal microleakage<br />
in both in vivo and in vitro models (Figs. 5 and 6). 26-29<br />
Coronal Seal<br />
After obturation, the placement of a coronal seal is absolutely<br />
correlated with clinical success in the endodontic literature.<br />
Such a seal could be achieved by using Maxcem (Kerr,<br />
Orange, CA, USA); a self adhesive and self-etching composite<br />
for build up procedures and/or coronal seal. Placement of<br />
the coronal seal should be accomplished without delay<br />
while the rubber dam is still on and before the patient is<br />
released from the treatment visit. Doing so will reduce the<br />
possibilities of vertical root fracture due to the lack of a<br />
coronal build up in addition to concerns of microleakage<br />
(Figs. 7-10).<br />
Conclusion<br />
A series of clinically relevant steps to enhance the clinical<br />
success of endodontic therapy has been presented with the<br />
goal of optimizing endodontic therapy as an alternative to<br />
extraction and the placement of implants. Emphasis has<br />
been placed on use of the surgical operating microscope,<br />
straight line access, patency, copious irrigation, frequent<br />
recapitulation, passive rotary nickel titanium file use,<br />
bonded obturation and placement of an early coronal seal.<br />
Acknowledgements<br />
The author does not have a financial interest in any of the<br />
products discussed in this article.
References<br />
1. Naito T. Better success rate for root canal therapy when treatment<br />
includes obturation short of the apex. Evid Based Dent. 2005;6(2):45.<br />
2. Siqueira JF Jr, Rôças IN, Alves FR, Campos LC. Periradicular status related<br />
to the quality of coronal restorations and root canal fillings in a Brazilian<br />
population. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2005<br />
Sep;100(3):369-74.<br />
3. Nair PN. Pathogenesis of apical periodontitis and the causes of endodontic<br />
failures. Crit Rev Oral Biol Med. 2004 Nov 1;15(6):348-81.<br />
4. Ørstavik D, Qvist V, Stoltze K. A multivariate analysis of the outcome of<br />
endodontic treatment. Eur J Oral Sci. 2004 Jun;112(3):224-30.<br />
5. Vianna ME, Horz HP, Gomes BP, Conrads G. In vivo evaluation of microbial<br />
reduction after chemo-mechanical preparation of human root canals<br />
containing necrotic pulp tissue. Int Endod J. 2006 Jun;39(6):484-92.<br />
6. Van der Sluis LW, Gambarini G, Wu MK, Wesselink PR. The influence of<br />
volume, type of irrigant and flushing method on removing artificially<br />
placed dentine debris from the apical root canal during passive ultrasonic<br />
irrigation. Int Endod J. 2006 Jun;39(6):472-6.<br />
7. De la Casa ML, Raiden G. A scanning electron microscopy evaluation<br />
of different root canal irrigating solutions. Acta Odontol Latinoam.<br />
2005;18(2):57-61.<br />
8. Ari H, Erdemir A. Effects of endodontic irrigation solutions on mineral<br />
content of root canal dentin using ICP-AES technique. J Endod. 2005<br />
Mar;31(3):187-9.<br />
9. Ari H, Erdemir A, Belli S. Evaluation of the effect of endodontic irrigation<br />
solutions on the microhardness and the roughness of root canal dentin.<br />
J Endod. 2004 Nov;30(11):792-5.<br />
10. Law A, Messer H. An evidence-based analysis of the antibacterial effec<br />
tiveness of intracanal medicaments. J Endod. 2004 Oct;30(10):689-94.<br />
11. Lin YH, Mickel AK, Chogle S. Effectiveness of selected materials<br />
against Enterococcus faecalis: part 3. The antibacterial effect of calcium<br />
hydroxide and chlorhexidine on Enterococcus faecalis. J Endod. 2003<br />
Sep;29(9):565-6.<br />
12. Gomes BP, Souza SF, Ferraz CC, Teixeira FB, Zaia AA, Valdrighi L, Souza-Filho<br />
FJ. Effectiveness of 2% chlorhexidine gel and calcium hydroxide against<br />
Enterococcus faecalis in bovine root dentine in vitro. Int Endod J. 2003<br />
Apr;36(4):267-75.<br />
13. Vivacqua-Gomes N, Ferraz CC, Gomes BP, Zaia AA, Teixeira FB, Souza-Filho<br />
FJ. Influence of irrigants on the coronal microleakage of laterally<br />
condensed gutta-percha root fillings. Int Endod J. 2002 Sep;35(9):791-5.<br />
14. Tanomaru Filho M, Leonardo MR, da Silva LA. Effect of irrigating solution<br />
and calcium hydroxide root canal dressing on the repair of apical and<br />
periapical tissues of teeth with periapical lesion. J Endod. 2002<br />
Apr;28(4):295-9.<br />
15. Averbach RE, Kleier DJ. Clinical update on root canal disinfection. Compend<br />
Contin Educ Dent. 2006 May;27(5):284, 286-9.<br />
16. De la Casa ML, Raiden G. A scanning electron microscopy evaluation<br />
of different root canal irrigating solutions. Acta Odontol Latinoam.<br />
2005;18(2):57-61.<br />
17. Zehnder M. Root canal irrigants. J Endod. 2006 May;32(5):389-98.<br />
18. Jenkins S, Kulild J, Williams K, Lyons W, Lee C. Sealing ability of three<br />
materials in the orifice of root canal systems obturated with gutta-percha. J<br />
Endod. 2006 Mar;32(3):225-7.<br />
19. Trope M, Chow E, Nissan R. In vitro endotoxin penetration of coronally<br />
unsealed endodontically treated teeth. Endod Dent Traumatol. 1995<br />
Apr;11(2):90-4.<br />
20. Ray HA, Trope M. Periapical status of endodontically treated teeth in<br />
relation to the technical quality of the root filling and the coronal restoration.<br />
Int Endod J. 1995 Jan;28(1):12-8.<br />
21. Barrieshi KM, Walton RE, Johnson WT, Drake DR. Coronal leakage of<br />
mixed anaerobic bacteria after obturation and post space preparation.<br />
Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 1997 Sep;84(3):310-4.<br />
22. Torabinejad M, Ung B, Kettering JD. In vitro bacterial penetration<br />
of coronally unsealed Endodontically treated teeth. J Endod. 1990<br />
Dec;16(12):566-9.<br />
23. Saunders WP, Saunders EM. Assessment of leakage in the restored pulp<br />
chamber of Endodontically treated multirooted teeth. Int Endod J. 1990<br />
Jan;23(1):28-33.<br />
24. Chailertvanitkul P, Saunders WP, Saunders EM, MacKenzie D. An evaluation<br />
of microbial coronal leakage in the restored pulp chamber of root canal<br />
treated multirooted teeth. Int Endod J. 1997 Sep;30(5):318-22.<br />
25. Swartz DB, Skidmore AE, Griffin JA. Twenty years of Endodontic success<br />
and failure. J Endod. 1983 May;9(5):198-202.<br />
26. Leonardo MR, Barnett F, Debelian GJ, de Pontes Lima RK, Bezerra<br />
da Silva LA. Root canal adhesive filling in dogs’ teeth with or without<br />
coronal restoration: a histopathological evaluation. J Endod. 2007<br />
Nov;33(11):1299-303. Epub 2007 Sep 17.<br />
27. Stratton RK, Apicella MJ, Mines P. A fluid filtration comparison of gutta-percha<br />
versus Resilon, a new soft resin endodontic obturation system. J Endod.<br />
2006 Jul;32(7):642-5.<br />
28. Shipper G, Teixeira FB, Arnold RR, Trope M. Periapical inflammation<br />
after coronal microbial inoculation of dog roots filled with gutta-percha<br />
or resilon. J Endod. 2005 Feb;31(2):91-6.<br />
29. Shipper G, Ørstavik D, Teixeira FB, Trope M. An evaluation of microbial<br />
leakage in roots filled with a thermoplastic synthetic polymer-based<br />
root canal filling material (Resilon). J Endod. 2004 May;30(5):342-7.
Forensic Dentistry<br />
Dr. Suhail Hani Al-Amad<br />
BDS, DCD, GradDip ForOdont,<br />
MRACDS (Oral Med), JMC<br />
cert. (Oral Med)<br />
. Assistant Professor of Oral<br />
Medicine,College of Dentistry,<br />
University of Sharjah<br />
suhail_amad@hotmail.com<br />
22 <strong>Smile</strong> <strong>Dental</strong> Journal Volume 4, Issue 1 - 2009<br />
Forensic Odontology<br />
Abstract<br />
Forensic Odontology is a relatively new science that utilizes the dentist’s knowledge to serve<br />
the judicial system. Worldwide, dentists qualified in forensic science are giving expert opinion<br />
in cases related to human identification, bitemark analysis, craniofacial trauma and malpractice.<br />
Human identification relies heavily on the quality of dental records; however Forensic Odontologists<br />
can still contribute to the identity investigation in the absence of dental records through<br />
profiling the deceased person using features related to teeth.<br />
Along with other healthcare providers, dentists encounter cases of injuries which could be<br />
non-accidental. Detection, interpretation and management are important from a legal and<br />
humanitarian point of view. Dentists should be aware of the legal impact those cases have,<br />
and should refer them to the appropriate authorities for suitable action.<br />
This article gives an insight to Forensic Odontology and outlines some of its medico-legal applications.<br />
Key words: Forensic Odontology, identification, violence, abuse.<br />
The roles of any forensic scientist are to collect, preserve and interpret trace evidence, then to<br />
relay the results to the judicial authority in a form of a report. Those functions require sound<br />
knowledge in dealing with crime scenes and sufficient acquaintance in law. Forensic Odontology<br />
is the forensic science that is concerned with dental evidence.<br />
The use of teeth as evidence is not recent. There are historical reports of identification by<br />
recognizing specific dental features as early as 49 A.C. However, Forensic Odontology, as a<br />
science, did not appear before 1897 when Dr. Oscar Amoedo wrote his doctoral thesis entitled<br />
“L’Art Dentaire en Medecine Legale” describing the utility of dentistry in forensic medicine<br />
with particular emphasis on identification. 1<br />
Traditionally, Forensic Odontology covered various topics that can be broadly classified into<br />
human identification and injury analysis. However, tasks of Forensic Odontologists have<br />
broadened in recent years to cover issues related to child abuse and domestic violence, human<br />
rights protection and professional ethics.<br />
This article gives a brief overview of some of the roles undertaken by Forensic Odontologists.<br />
Human Identification<br />
Identification is based on comparison between known characteristics of a missing individual<br />
(termed ante-mortem data) with recovered characteristics from an unknown body (termed<br />
post-mortem data).<br />
Identification of the deceased is most commonly achieved visually by a relative or a friend<br />
who knew the person during life. This is performed by looking at characteristics of the face,<br />
various body features and/or personal belongings. However, this method becomes undesirable<br />
and unreliable when the body features are lost due to post- and peri-mortem changes (such<br />
as decomposition or incineration). Visual identification in those circumstances is subject to error.<br />
Methods of human identification that are acknowledged as scientific are fingerprint, DNA,<br />
dental and medical characteristics. 2 Those methods vary in complexity, but share similar level<br />
of certainty. The dental characteristics method is unique in being the easiest and quickest<br />
method of identification.<br />
The diversity of dental characteristics is wide, making each dentition unique. 3 The dental<br />
enamel is the hardest tissue in the body, and would thus withstand peri- and post-mortem<br />
damages, and so would dental materials adjoined to teeth. Being diverse and resistant to<br />
environmental challenges, teeth are considered excellent post-mortem material for identification
with enough concordant points to make a meaningful comparison.<br />
For dental identification to be successful, ante-mortem data<br />
need to be available. This relies heavily on dental professionals<br />
recording and keeping dental notes, radiographs, study<br />
models, clinical photographs…etc. The availability of dental<br />
records will allow comparing the dental characteristics of the<br />
person during life with those retrieved from the person<br />
after death (Fig. 1).<br />
In cases where dental records are not available, Forensic<br />
Odontology can still contribute to establishing the identity<br />
by creating a profile of how the deceased person was during<br />
life. This includes any unusual oral habits, type of diet,<br />
socio-economic status, but most importantly the age of the<br />
person at time of death.<br />
<strong>Dental</strong> aging is based on the chronology of formation and<br />
eruption of teeth. This helps in determining the age for persons<br />
up to 15 years-old in a fairly accurate manner. After 15 years<br />
of age, dental aging relies on modifications that take place<br />
during life, such as attrition, cementum formation and root<br />
transparency. 4 Despite being extensively studied, results of<br />
aging of this latter group remain less than optimal because<br />
those age-related modifications can be influenced by various<br />
factors, such as diet and dental pathosis. 4<br />
Dentists’ Role in Mass Fatality Incidences<br />
Routine identification tasks are a simple one-to-one matching<br />
process. This is not the case in disasters. Mass fatality<br />
incidences represent a big challenge to local authorities.<br />
Another challenge is the damage inflicted on infra-structure<br />
that includes hospitals, transportation, communications…<br />
etc. which impede recovery.<br />
The identification of deceased victims in those circumstances<br />
necessitates putting a hierarchy system consisting of an<br />
ante-mortem, post-mortem and reconciliation teams. Those<br />
teams are headed by team leaders, with liaison officers to<br />
coordinate the work. The results are reported to an identification<br />
board which is headed by a commander, who in most cases<br />
is a senior police officer.<br />
Forensic Odontologists have contributed to the resolution<br />
of many mass disasters. The 2004 Indian ocean tsunami<br />
is probably the most eminent example on the success<br />
of Forensic Odontologists in identifying large number of<br />
victims in short time. Nearly half of the victims in Thailand<br />
were identified by dental characteristics method alone, and<br />
Forensic Odontologists contributed to the identification<br />
of the remaining half by assisting the fingerprint, DNA and<br />
physical characteristics teams.<br />
Weak, and even absence of dental records did not stop<br />
Forensic Odontologists from contributing to the identification<br />
of tsunami victims in Thailand. Victims with no dental<br />
records were either identified by photographic superimposition,<br />
if a photograph showing upper anterior teeth was provided5 (Fig. 2), or by narrowing down possible matches for the<br />
DNA and fingerprint teams through dental aging.<br />
Bitemark Analysis<br />
Injuries induced by teeth and left on objects, such as skin,<br />
have a distinctive pattern. Those patterned injuries (bitemarks)<br />
are useful to judicial authorities because they help in reconstructing<br />
(Figure 1)<br />
Ante-mortem radiograph<br />
taken by the treating<br />
dentist and post-mortem<br />
radiograph taken by the<br />
Forensic Odontologist<br />
of the unknown<br />
deceased. There are<br />
many concordant points<br />
to establish a positive<br />
identification.<br />
(Figure 2)<br />
Identification by photo-skull<br />
superimposition. The<br />
skull of an unknown<br />
child was superimposed<br />
onto the portrait of a<br />
missing person. The<br />
outline of teeth and<br />
the facial anatomical<br />
similarities suggested<br />
that the skull belongs to<br />
the child in the portrait.<br />
The right central incisor<br />
in the skull was lost after<br />
death.<br />
past events that surrounded the biting process. For example,<br />
bitemarks indicate a violent interaction between the<br />
perpetrator and the victim, and they might tell us something<br />
about the criminal intentions of the perpetrator, whether sexual,<br />
child abuse, or other forms of assaults. Moreover, bitemarks<br />
are the only patterned injuries that can indicate (with different<br />
levels of certainty) who the biter was. By comparing the<br />
locations and measurements of teeth marks in a bitemark<br />
with those of the suspect(s), Forensic Odontologists can<br />
exclude or include persons suspected of causing the bitemarks.<br />
However, several erroneous bitemark analysis, mainly from<br />
the United States courts, rendered this type of evidence<br />
<strong>Smile</strong> <strong>Dental</strong> Journal Volume 4, Issue 1 - 2009<br />
23
Forensic Dentistry<br />
questionable. 6 The validity of bitemark analysis has undergone<br />
decent review in the last ten years aiming at boosting the<br />
scientific weight and improving the technique in a manner that<br />
can be reproducible. <strong>New</strong> research is underway to allow<br />
digital comparison of teeth and bitemarks at a 3-dimensional level. 7<br />
This novel technique is aimed to overcome perspective<br />
distortion, a significant morbid factor in bitemark analysis that<br />
results from reducing 3-dimensional objects to 2-dimensional<br />
images.<br />
Domestic Violence and Child Abuse<br />
The World Health Organization (WHO) has declared that violence<br />
is a major and growing public health problem across the<br />
world. 8 This landmark declaration meant that healthcare<br />
providers are involved in detecting and managing cases<br />
of violence, including abuse to vulnerable populations, i.e.<br />
children, elderly and women.<br />
The WHO further distinguishes four types of violence; physical,<br />
sexual, psychological and neglect. All forms of violence can<br />
manifest in the oro-facial region, and are hence should be<br />
of concern to dentists. Prevalence of physical violence, as a<br />
cause of maxillofacial injuries, ranges from 3.3% to 41% in<br />
various countries. 9 This wide range is probably due to different<br />
reporting thresholds in different communities. The true<br />
prevalence of violence is thus difficult to establish because<br />
of not or under-reporting this problem.<br />
Injuries due to abuse can manifest in the oro-facial region in<br />
various forms, including fractured anterior teeth, fractured<br />
alveolar bone, lacerations of the labial and buccal mucosae,<br />
lacerations to the frenum and bruises to the lips, face and<br />
neck (Fig. 3). Non-accidental injuries have certain characteristics<br />
which help in their recognition (Table 1). 10<br />
The most common site to be non-accidentally traumatized<br />
is the head. 11 Therefore, injuries to the oro-facial region<br />
should raise reasonable suspicion to the treating dentist.<br />
Suspicion should lead to investigation and reporting, but<br />
the reporting must be well-thought of. On one hand, there<br />
is a necessity to report those cases to authorities. But on the<br />
other hand, reporting false cases is stigmatizing and is an<br />
unacceptable interference in the victim’s personal affairs.<br />
In various countries there are laws that govern reporting of<br />
violence. Some laws penalize healthcare workers by<br />
imprisonment, and/or fines, for not reporting violence manifested<br />
on their patients. 12,13 However, due to the sensitivity of this<br />
matter, reporting has to follow a sound mechanism, and be<br />
addressed to a proper authority with specifically-trained<br />
personnel. Readers are advised to search for the proper<br />
reporting authority in their respective countries.<br />
Conclusion<br />
<strong>Dental</strong> practitioners should be aware of the forensic application<br />
of dentistry. <strong>Dental</strong> records that are used to provide patients<br />
with optimal dental service could also be very beneficial to<br />
legal authorities during an identification process. Therefore,<br />
all forms of dental treatments should be recorded and kept<br />
properly. <strong>Dental</strong> clinicians, as other healthcare workers, are<br />
at the forefront in detecting signs of violence appearing<br />
on their patients. They should be aware of the criteria of<br />
abusive injuries, and the reporting mechanisms to ensure a<br />
correct response by the concerned authorities.<br />
24 <strong>Smile</strong> <strong>Dental</strong> Journal Volume 4, Issue 1 - 2009<br />
(Figure 3)<br />
Lacerated injury on the<br />
upper lip of a child after<br />
a smothering attempt<br />
(Courtesy of Dr. Mumen S.<br />
Haddidi).<br />
References<br />
1. Bernstein M. Forensic odontology. In: Eckert WG. editor. Introduction to<br />
Forensic Sciences. 2 nd ed. Boca Raton, FL: CRS Press; 1997, p. 304-51.<br />
2. Interpol. Disaster victim identification. Available at: URL:http://www.<br />
interpol.int/Public/DisasterVictim/default.asp. Accessed 5 th Feb 2009.<br />
3. Adams BJ. Establishing personal identification based on specific<br />
patterns of missing, filled, and unrestored teeth. J Forensic Sci. 2003<br />
May;48(3):487-96.<br />
4. Meinl A, Huber CD, Tangl S, Gruber GM, Teschler-Nicola M, Watzek G.<br />
Comparison of the validity of three dental methods for the estimation of<br />
age at death. Forensic Sci Int. 2008 Jul 4;178(2-3):96-105. Epub 2008 Apr 8.<br />
5. Al-Amad S, McCullough M, Graham J, Clement J, Hill A. Craniofacial<br />
identification by computer-mediated superimposition. J Forensic<br />
Odontostomatol. 2006 Dec;24(2):47-52.<br />
6. Bowers CM. Problem-based analysis of bitemark misidentifications: the<br />
role of DNA. Forensic Sci Int. 2006 May 15;159 Suppl 1:S104-9. Epub<br />
2006 Apr 4.<br />
7. Blackwell SA, Taylor RV, Gordon I, Ogleby CL, Tanijiri T, Yoshino M, et al.,<br />
3-D imaging and quantitative comparison of human dentitions and<br />
simulated bite marks. Int J Legal Med. 2007 Jan;121(1):9-17. Epub 2006 Jan 4.<br />
8. World Health Organization. Prevention of violence: a public health problem.<br />
49 th World Health Assembly Resolution WHA49.25: Geneva: WHO, 1996.<br />
9. Eggensperger N, Smolka K, Scheidegger B, Zimmermann H, Iizuka T. A.<br />
3-year survey of assault-related maxillofacial fractures in central Switzerland. J<br />
Craniomaxillofac Surg. 2007 Apr;35(3):161-7. Epub 2007 Jun 20.<br />
10. Mok JY. Non-accidental injury in children--an update. Injury. 2008<br />
Sep;39(9):978-85. Epub 2008 Jul 25.<br />
11. Maguire S. Bruising as an indicator of child abuse: when should I be<br />
concerned? Paediatrics and Child Health. 2008 Dec;18(12):545-9.<br />
12. Government of Dubai. Article 273 Federal Penalties Law of the UAE<br />
Number 3. 1987. Available at:URL:http://www.dc.gov.ae. Accessed 5 th<br />
Feb 2009.<br />
13. Jordanian Legislations. Article 207 Penalties Law of Hashemite Kingdom of<br />
Jordan. 1960. Available at:URL:http://www.lob.gov.jo. Accessed 5 th Feb 2009.
Implantology<br />
Dr. Philippe Tardieu<br />
DDS, PG in Implantology<br />
. Adjunct Associate Professor<br />
<strong>New</strong> York University<br />
. Founder and owner of<br />
Accuracy Current<br />
Technologies (ACT)<br />
. Founder and President<br />
of One-million <strong>Smile</strong>s, a<br />
French NGO.<br />
. Private Practice Dubai, UAE<br />
pt@frenchdentistdubai.com<br />
Immediate <strong>Smile</strong>® Procedure<br />
A Clinical Case Report<br />
26 <strong>Smile</strong> <strong>Dental</strong> Journal Volume 4, Issue 1 - 2009<br />
Abstract<br />
Improvement of implantology driven by computers deeply changed our point of view to treat<br />
patients. Using a CT-scan based planning system; the surgeon is able to select the optimal<br />
location for implant placement. Precise osteotomy control is performed using stereo-lithographic<br />
surgical guides. The SAFE System® is a serial instrumentation allowing transfer of planned<br />
implant positions to the mouth. Accuracy in implant placement is such that it allows not<br />
flapless implant placement with a submillimetric precision. Pain and swelling are minimized<br />
using trans-mucosal approach. Since 2002, vertical control of implant placement by the SAFE<br />
System® opened the way to the Immediate <strong>Smile</strong>® protocol. The prosthesis is made before the<br />
surgery without taking an impression and placed in the mouth during the same appointment<br />
as the surgery. The unique part of this procedure comes from the fact that the temporary<br />
bridge is screw retained on the implants without being relined and without using fancy and<br />
expensive components. The Immediate <strong>Smile</strong>® technique and components are introduced in<br />
this article and a clinical case illustrates the process.<br />
Key words: Computer-guided implantology, surgical guide, immediate smile, immediate loading.<br />
Since the 1990’s, several medical teams approached the problem of implant cases planning<br />
with the assistance of computer applications. 1-3 More recently other teams were in search of<br />
methods to transfer the data from the computer right to the mouth of the patients. 4,5<br />
Several systems have been designed to allow for an accurate transfer of planned data from<br />
the computer to the mouth of the patients at the time of implant placement. 6-9 Within the<br />
framework of the European Personalized Implants & Surgical Aids (PISA) project, several<br />
industrial companies and universities (Materialise, Philips Medical, Ceka, OBL, DuPuy International,<br />
Katholieke Universiteit Leuven, University of Leeds) have pooled their knowledge between<br />
1997 and the beginning of 2001. This led to the evolution of computer programs for the<br />
planning of implants and the design of custom made stereo-lithographic drill guides: the<br />
ScannoGuides® which is fabricated at the dental lab. This is what is called Computer Guided<br />
Implantology. This format was first validated on cadavers and in 1999 human clinical applications<br />
started. As part of this, we have tested different kinds of situations; partial or total cases, maxillary<br />
or mandibular restorations, implants with vertical or lateral insertion, implants in extended<br />
bone grafts, classical (in 1 or 2 surgical times) and immediate loading protocols, placement of<br />
implants throughout the bone or mucosa and at last, placement of zygomatic, pterygoid and<br />
sphenoid implants. 10,11<br />
We rapidly became aware that the tools of “classical” implantology were not adapted to this<br />
new approach and again accuracy, security and easiness were required during the novel<br />
implant placement approach. This reflection has become a major step towards the finalization<br />
of the SAFE System. 12,13<br />
The SAFE System was so accurate that it lead us to ovoid elevating flaps during implant placement<br />
and thus keeping intact the supracrestal vasculature and allowing real micro access surgery to<br />
be performed in oral implantology. 14 Choosing the proper dense bone available also allowed<br />
us to better stabilize implants and immediately load them. The missing link at that time was<br />
the way to fabricate a screw-retained bridge prior to implants placement. We did not want to<br />
reline the bridge (unless necessary) and we wanted the bridge to be immediately placed into<br />
the patient’s mouth during the same appointment at implant placement.<br />
Since 2002 and to achieve this goal we developed with Materialise <strong>Dental</strong> collaboration<br />
(Materialise <strong>Dental</strong>, Leuven, Belgium) the Immediate <strong>Smile</strong> procedure and components.The<br />
procedure is in this article explained and illustrated by a clinical case.
Case Report<br />
An elderly patient was unhappy with his lower denture after<br />
the recent extraction of his last lower anterior hopeless<br />
teeth (Figs. 1 and 2). He wished to recover a good function.<br />
An Immediate <strong>Smile</strong> procedure was proposed to him to get<br />
a functional result with minimum intervention and time.<br />
ScannoGuide®<br />
The scannographic template not only allows the transfer of<br />
the predetermined prosthetic set up to the actual implant<br />
planning but also gives us an image of the underlying soft<br />
tissue. Incorporation of the scanning template in the CT<br />
scanning data allows the surgeon to base his implant planning<br />
on the desired prosthetic outcome. The treatment plan is a<br />
synthesis of existing information between bone and teeth<br />
to be replaced. The scannographic template is built out of a<br />
duplicate of the denture of the patient (Fig. 3). For a full arch<br />
reconstruction we use a 30% barium sulfate and resin mix in<br />
weight for teeth and a 10% mix for the base. On the<br />
scannographic template, the main axis of the tooth is<br />
marked by drilling a cylindrical shaft in the tooth, centered<br />
on its occlusal side and emerging at the center of the cervical<br />
surface (Fig. 4). On the scanning images, this cylindrical<br />
shaft is easily visualized.<br />
CT Scanning and Data Conversion<br />
The patient was sent to the radiologist together with the<br />
scannographic template. The CT scan quality is of major<br />
importance. Not only implant placement planning and transfer<br />
will be based on these data, but the Immediate <strong>Smile</strong><br />
prosthesis will be also fabricated depending on these data.<br />
After the scan was completed, the radiologist sent the data<br />
to a “data processing center”. A computer engineer edits the<br />
images by removing scattered images and useless parasite<br />
images such as the spinal column, antagonist teeth and ramus<br />
of the mandible when working on a maxillary analysis. The<br />
scanning template can be easily identified in axial sections.<br />
Different anatomic structures such as the maxilla and<br />
mandible and the scannographic template are separated in<br />
different masks. Each of these masks can be toggled on or<br />
off to allow separate visualization and interpretation.<br />
Implant Position Planning<br />
The SimPlant software provides four planes in which it is<br />
possible to modify the outline and display resolution at<br />
one’s convenience (Fig. 5). Each of these planes displays<br />
either the sections at the gray level, or the 3D color<br />
reconstructions. The 3D reconstructions allow seeing the<br />
lingual emergence of the implants, the inferior alveolar<br />
nerve path and the plan of the three retention screws we<br />
(Figure 1)<br />
The clinical case before<br />
extraction of the lower<br />
hopeless anterior teeth.<br />
(Figure 2)<br />
The fabricated lower<br />
denture was used to<br />
change the anterior<br />
guidance during a healing<br />
period of 8 weeks.<br />
(Figure 3)<br />
Denture duplicate used as<br />
a scannographic template.<br />
(Figure 4)<br />
Cylindrical shafts at the<br />
main axis of the teeth.<br />
(Figure 5)<br />
SimPlant software showing<br />
four planes of the scanned<br />
images.<br />
(Figure 6-7)<br />
3D reconstructions showing masks of the inferior<br />
alveolar nerves, masks of the base plate of the<br />
denture and of the teeth of the denture. Note that<br />
not only implants have been planned but also<br />
retention screws to stabilize the surgical guide during<br />
implant placement.<br />
<strong>Smile</strong> <strong>Dental</strong> Journal Volume 4, Issue 1 - 2009<br />
27
Implantology<br />
(Figure 8)<br />
Implants’ planned<br />
positions and retention<br />
screws’ positions can<br />
be fine tuned on the 3D<br />
display before sending an<br />
order for a surgical guide.<br />
(Figure 9)<br />
Immediate smile<br />
components including IS<br />
cylinder, centering screw,<br />
retention screw, implant<br />
analogue with flat surface<br />
and internal retention and<br />
a sample of an implant.<br />
(Figure 10)<br />
SAFE System implant<br />
holder and Implant<br />
analogue.<br />
(Figure 11)<br />
3D image of the planned<br />
mucosa-supported<br />
surgical guide SAFE<br />
System.<br />
(Figure 12)<br />
Surgical guide placed<br />
over the lower jaw<br />
stereolithographic model.<br />
This is done to position<br />
the implant analogues and<br />
fabricate the Immediate<br />
<strong>Smile</strong> screw retained<br />
temporary bridge.<br />
(Figure 13)<br />
The Surgical guide<br />
is perfectly adapted<br />
to the surface of the<br />
stereolithographic jaw<br />
model which includes the<br />
soft tissue.<br />
28 <strong>Smile</strong> <strong>Dental</strong> Journal Volume 4, Issue 1 - 2009<br />
planned to use to stabilize the surgical guide (Figs. 6 and 7).<br />
The surgeon is able to view the implant project 3D color<br />
reconstructions and play with 3D images which are called<br />
“masks”. The position of the implant can then be fine-tuned<br />
by shifting, tilting or by adaptation of its dimensions in a<br />
panoramic reconstruction plane (Fig. 8).<br />
The software has some semi-automatic functions to help<br />
the surgeon in placing a newly planned implant between<br />
two other previously placed implants. Another function<br />
helps the surgeon in translating an implant over a certain<br />
amount of space along a predefined curve. The remarkable<br />
versatility of the software in manipulation of the implants<br />
thus helps the surgeon to choose optimal locations for the<br />
implants according to a complex set of prerequisites,<br />
correspondence with the initial prosthetic plan, visual check<br />
that the implant is in all directions encased in bone, optimal<br />
position so that the implant is in a zone with the highest<br />
possible Hounsfield unit value which is correlated to the<br />
biomedical characteristics of the bone namely its hardness.<br />
Pre-Surgical Fabrication of the Immediate <strong>Smile</strong> Bridge<br />
For the lab procedure, the following components are used<br />
(Figs. 9 and 10)<br />
• An immediate smile (IS) cylinder to fabricate the screw<br />
retained temporary bridge.<br />
• A centering screw allowing correct placement of the IS<br />
cylinder on the implant analogues in the laboratory.<br />
• An IS implant analogue. In certain cases we have been using<br />
fake IS implants and the comparison of these different protocols<br />
will be published in a fore coming article.<br />
• An IS screw, specially designed to allow a horizontal<br />
displacement of plus or minus 0.5 mm around the ideal<br />
implant position.<br />
• An IS implant presenting an internal hex and a flat surface<br />
allowing a horizontal adaptation with the IS cylinder.<br />
• SAFE System implant holders of the pre determined length.<br />
The final bridge is fabricated using standard components.<br />
It is fabricated on a stereo-lithographic model of the jaw<br />
provided by Materialise. This model includes the soft tissue<br />
on implant emergence area. The surface of the soft tissue<br />
is found using the underlying surface of the ScannoGuide.<br />
Holes are pre-prepared to allow placement of implant<br />
analogues (Fig. 11). A surgical guide is pre planned with implants<br />
and retention screws positions (Fig. 12). The surgical guide<br />
is snapped on the stereolithographic jaw model. The Surgical<br />
guide is also used to position implant analogues in the jaw<br />
model. We can notice the perfect adaptation of the SurgiGuide<br />
on the stereo-lithographic model (Fig. 13).<br />
Implants’ analogues are placed using the SAFE System implants’<br />
mounts through the SurgiGuide which has been stabilized<br />
using osteosynthesis screws (Fig. 14). The analogues are<br />
glued from the bottom of the holes to be stabilized inside<br />
the stereo-lithographic model (Fig. 15).<br />
The jaw is mounted in occlusion using the Scannoguide.<br />
The Immmediate <strong>Smile</strong> (IS) cylinders are placed on the<br />
analogues using the centering screws to fabricate the temporary<br />
bridge (Fig. 16). The SurgiGuide is controlled in the mouth using a<br />
resin template to check the final occlusion, then the bridge is<br />
fabricated and retained with the IS screws (Figs. 17 and 18).<br />
We found out that the accuracy of the SAFE System is such
that the vertical precision is good enough not to use special<br />
components for that. The Immediate <strong>Smile</strong> components will<br />
correct a horizontal error of plus or minus 0.5 mm all around<br />
the ideal implant position. The design of the Immediate<br />
<strong>Smile</strong> screws and cylinders allows this horizontal adaptation.<br />
We can notice that the simplicity of these components is<br />
evident and particularly adapted to screw retrained bridges.<br />
This is only possible once the whole chain of accuracy of<br />
Computer Guided Implantology has been respected. We<br />
talk about a submillimetric accuracy that is actually impossible<br />
to appreciate visually. The surgeons need to go through a<br />
learning curve using these systems prior to performing an<br />
Immediate <strong>Smile</strong> procedure. The more implants support the<br />
bridge the more difficult the case will be.<br />
Implants and Bridge Placement<br />
The finalized treatment plan is used for the fabrication of<br />
a surgical drill guide, with bone, mucosal or teeth support.<br />
The drill guide is produced by stereolithography (USP Class<br />
VI approved resin which is a US norm used for surgical components)<br />
containing medical grade stainless steel tubes. The position<br />
and direction of the cylinders correspond exactly to the<br />
position and direction of the planned implants.<br />
The SAFE System is incorporated in the SurgiGuide. This<br />
system allows the use of drills as well as implant placement<br />
guidance through one and only SurgiGuide. SAFE is the<br />
acronym of Secure, Accurate, Flexible and Ergonomic. It<br />
contains a set of new cylinders to guide not only drilling,<br />
but also to drive the implants in position after drilling. It<br />
also includes new drills, limited to a pilot drill and a final<br />
drill with a flange to introduce depth control. It includes<br />
new implant holders to allow perfect positioning, angulations<br />
and depth of the implants. Some other instruments such as<br />
trephines to remove soft tissue or different kind of taps can<br />
be used too.<br />
One of the major advantages of using SAFE-SurgiGuides<br />
is the exact transfer of implant positions to the mouth. We<br />
have been using a variety of systems to do that. Accuracy<br />
of transfer has been studied by the author and will be soon<br />
published in a book under the title “The Art of Computer-guided<br />
Implantology” by P. Tardieu and A. Rosenfled by Quintessence<br />
publishing, 2009.<br />
The mucosal SAFE-SurgiGuide is in this case directly stabilized<br />
using an occlusal template and secured by several<br />
osteosynthesis screws to prevent it from moving during surgery.<br />
Stabilization of the SAFE-SurgiGuide is mandatory to ensure<br />
accuracy of implant placement and accuracy of the inter-arch<br />
position. With the SAFE System, implants are accurately<br />
placed in position, angulations as well as in depth. Depth<br />
control is done by using a flange<br />
on drills and implants’ mounts<br />
allowing exact implant placement.<br />
A detailed plan was received<br />
setting the SAFE System drill<br />
and implants’ mounts choice<br />
(Fig. 19). Intra-orally, it can be<br />
readily seen that the mandibular<br />
crest is highly resorbed and<br />
(Figure 14)<br />
SAFE system implant<br />
holders are used to<br />
position the implant<br />
analogues inside the jaw<br />
model.<br />
(Figure 15)<br />
Implant analogues are<br />
glued in the jaw model.<br />
(Figure 16)<br />
Centering screws are used<br />
to center the IS cylinders<br />
on top of the implant<br />
analogues.<br />
(Figure 17)<br />
The jam model is mounted<br />
on an articulator using<br />
the ScannoGuide first and<br />
then the temporary bridge<br />
is fabricated.<br />
(Figure 18)<br />
Top view of the 10 teeth<br />
temporary screw retained<br />
bridge showing the space<br />
around the top of the<br />
retention screws. This is<br />
done to allow a horizontal<br />
deviation of 0.5 mm if<br />
needed.<br />
(Figure 19)<br />
This guiding sheet drives<br />
the surgeon to select<br />
the right SAFE drills and<br />
SAFE implant holders to<br />
place the implant in a<br />
very accurate position (30<br />
microns).<br />
<strong>Smile</strong> <strong>Dental</strong> Journal Volume 4, Issue 1 - 2009<br />
29
Implantology<br />
(Figure 20)<br />
This figure explains the<br />
way height of drills and<br />
implant holders are<br />
selected based on the<br />
Regulator distance which<br />
is the distance between<br />
the top of the implant to<br />
the bottom of the guiding<br />
cylinder.<br />
(Figure 21)<br />
View of the lower jaw<br />
before starting the surgery.<br />
Note the highly resorbed<br />
bone.<br />
(Figure 22)<br />
SAFE System guide is<br />
placed and secured on the<br />
mucosa using retention<br />
screws. A trephine is used<br />
to remove the soft tissue<br />
before using drills.<br />
(Figure 23)<br />
Accurate implants<br />
placement through the<br />
SurgiGuide isunh SAFE<br />
System implant holders.<br />
(Figure 24)<br />
After implant placement,<br />
the surgical guide is<br />
removed showing the top<br />
of implants. No sutures are<br />
needed at that step.<br />
(Figure 25)<br />
Immediate Insertion of the<br />
presurgically fabricated<br />
bridge.<br />
30 <strong>Smile</strong> <strong>Dental</strong> Journal Volume 4, Issue 1 - 2009<br />
the floor of the mouth is close to the level of the crest (Fig.<br />
21). The SurgiGuide SAFE System is placed on the mucosa<br />
and the position with the opposite arch is checked with the<br />
resin template. A 4.0 mm trephine is engaged inside the<br />
titanium guiding cylinders to remove tissues from on top<br />
the osteotomy sites to avoid any soft tissue contamination<br />
during the procedure. We can notice that the guide is securely<br />
stabilized using three retention screws (Fig. 22). Drilling<br />
for implants’ placement is then proceeded and precisely<br />
controlled by SurgiGuide SAFE System. The procedure is not<br />
finished after implant placement (Fig. 23). The prefabricated<br />
bridge should be now seated into the patient’s mouth.<br />
The SurgiGuide is unscrewed, removed and the implants<br />
can be readily seen (Fig. 24). The pre-fabricated bridge is<br />
first placed on one screw without screwing it in depth. Once<br />
all screws are in position, all of them can then be screwed to<br />
the full depth. Very limited occlusal adjustments are usually<br />
requested (Fig. 25) and a panoramic x-ray is taken to check<br />
the adaptation of the bridge on the implants (Fig. 26). We<br />
can appreciate on figure 27 the difference of position of<br />
screws from one cylinder to another one. If a lack of adaptation<br />
appears on one or several implants, it is always simple to<br />
unglue a cylinder, to screw it back on the implant and to<br />
glue it again into the resin bridge in a limited time.<br />
This procedure gives patients an unparallel service that is<br />
highly appreciated due to the limitation of time and of post<br />
operative complications and pain. Within 8 weeks, after implant<br />
validation a 12-teeth-bridge with a metal framework is<br />
performed (Fig. 28).<br />
Discussion<br />
Since a long time, several different teams proposed a short<br />
time delivery of a prosthesis, by relining or adapting a<br />
previously made bridge or by very fast fabrication of the<br />
prosthesis. Immediate <strong>Smile</strong> procedure is an immediate<br />
screw-retained prosthesis with as limited oral interventions<br />
as possible, no implant impressions, no transfer of occlusion<br />
from the mouth and no relining. To reach this goal we need<br />
to have good control over certain number of points.<br />
1. One needs to have good control over immediate loading<br />
procedures. The surgeon and his team, including the lab<br />
technician, need certain clinical experience to be comfortable<br />
with these procedures.<br />
2. One should be able to transfer implant position and<br />
angulation from a computerized plan to the mouth with<br />
submillimetric accuracy. In the case of computer guided<br />
implantology, this can be achieved by respecting the<br />
whole chain of accuracy using ScannoGuide, SimpPlant<br />
software and SurgiGuide SAFE System.<br />
3. One should be able to control the depth of implants
Implantology<br />
(Figure 26)<br />
Excellent adaptation of the<br />
IS cylinders to the implants<br />
as demonstrated by a<br />
panoramic x-ray.<br />
(Figure 27)<br />
Lingual view of the<br />
Immediate <strong>Smile</strong> bridge,<br />
screw retained on top of<br />
the flat implants. Note the<br />
lateral deviation of screws<br />
allowed by the design of<br />
the IS retention screws and<br />
cylinders.<br />
(Figure 28<br />
The bridge after two years<br />
of insertion.<br />
independent of the kind of surgical guide used; bone,<br />
mucosa or tooth supported. This is done with measures<br />
that the surgeons receive from Materialise on the guiding<br />
sheet showing the drill lengths and implants’ mounts<br />
lengths that should be used for every single implant.<br />
4. One should be able to fabricate a prosthesis at the lab<br />
prior to the surgery using a lab model including the<br />
transfer of implants’ analogues. Materialise can provide a<br />
stereo-lithographic model with reservations for implantanalogue<br />
placement. This model can be mounted on the<br />
articulator using the scannographic guide (ScannoGuide),<br />
to transfer the occlusion. Accordingly, all the required elements<br />
to be able to fabricate the immediate temporary prosthesis<br />
are present.<br />
5. It should be possible to overcome some minor differences<br />
between implant positioning plan and real implant position<br />
in the mouth. Certain Immediate <strong>Smile</strong> components have<br />
been developed for this purpose. These components<br />
allow a difference of circa half a millimeter. We should<br />
notice that the difference between implant positions is<br />
often very small as long as implants are driven in position<br />
by the guiding cylinders of the SAFE System.<br />
Since our first trials in 2002, we have been doing a wide variety<br />
of cases; full upper and lower cases, partial upper and lower<br />
cases. In our learning curve, not all cases went out perfectly<br />
at once, but we improved very fast with the help of different<br />
tools available at Materialise. The more implants we have<br />
the more difficult it is to adapt all of them without any modification.<br />
Immediate <strong>Smile</strong> is the knife hedge knowledge in this<br />
field and brings several benefits to our patients and to the<br />
32 <strong>Smile</strong> <strong>Dental</strong> Journal Volume 4, Issue 1 - 2009<br />
surgical team. Immediate <strong>Smile</strong> allows us to work securely<br />
because we can get submillimetric accuracy in implant<br />
placement. This procedure is very efficient because in one<br />
appointment not only the surgery is performed but also the<br />
bridgework is delivered. Pain is limited to nearly nothing.<br />
Working through the mucosa avoids flap elevation, sutures<br />
and keeps the supra-crestal vasculature intact to keep the<br />
underlying bone intact.<br />
Conclusion<br />
Progress in medical imaging and data processing are creating<br />
profound changes in the way professional practice is perceived.<br />
Treatments are becoming more precise, faster and safer for<br />
the patients. Surgeons are also able to better control<br />
and carry them out. The precision of implant positioning<br />
also helps in reducing the cost of prosthetic restorations<br />
avoiding the use of additional abutments to realign implants.<br />
The overall result is very gratifying for the patient and the<br />
implant team as a whole. Ongoing studies and new protocols<br />
are constantly emerging in computer guided implantology.<br />
References<br />
1. Schwarz MS, Rothman SL, Rhodes ML, Chafetz N. Computed tomography:<br />
Part I. Preoperative assessment of the mandible for endosseous implant<br />
surgery. Int J Oral Maxillofac Implants. 1987 Summer;2(3):137-41.<br />
2. Schwarz MS, Rothman SL, Rhodes ML, Chafetz N. Computed tomography:<br />
Part II. Preoperative assessment of the maxilla for endosseous implant<br />
surgery. Int J Oral Maxillofac Implants. 1987 Summer;2(3):143-8.<br />
3. Rothman SL, Chaftez N, Rhodes ML, Schwarz MS. CT in the<br />
preoperative assessment of the mandible and maxilla for endosseous<br />
implant surgery. Work in progress. Radiology. 1988 Jul;168(1):171-5.<br />
4. Mole C, Gerard H, Bouchet P, Della Malva R, Corbel S, Miller N, penaud<br />
J. Imagerie médicale exploitations et perspectives modélisation 3-D et<br />
reconstruction plastique stéréolithographique. Actualités odontostomatologiques.<br />
L’encyclopédie du praticien. 1993, no 181 (34 ref.), pp. 127-141.<br />
5. Klein M, Abrams M. Computer-guided surgery utilizing a computer-milled<br />
surgical template. Pract Proced Aesthet Dent. 2001 Mar;13(2):165-9; quiz 170.<br />
6. Molé C, Gérard H, Mallet JL, Chassagne JF, Miller N.A new threedimensional<br />
treatment algorithm for complex surfaces: applications in<br />
surgery. J Oral Maxillofac Surg. 1995 Feb;53(2):158-62.<br />
7. Philippe B, Tardieu P. Edentement complet maxillaire avec atrophie<br />
osseuse terminale : Prise en charge thérapeutique. A propose d’un cas<br />
Partie 1 Phase chirurgicale: principes thérapeutiques et indications.<br />
Implant. 2001;7:99-111.<br />
8. Tardieu P, Philippe B. Edentement complet maxillaire avec atrophie<br />
osseuse terminale : Prise en charge thérapeutique. A propose d’un cas<br />
Partie 2 Réalisation implantaire et prothétique: l’implantologie assistée<br />
par ordinateur. Implant. 2001;7:199-210.<br />
9. Vrielinck L, Wouters K, Wivell C, Dhoore E. Further development of drilling<br />
templates for the placement of regular dental implants and zygomatic<br />
fixtures, based on preoperative planning on CT images. In: Lemke HU,<br />
Vannier MW, Inamura K, Farman A, editors. Computer assisted<br />
radiology and surgery. Berlin, Germany: Elsevier Science; 2000, p. 945-49.<br />
10. Vrielinck L, Politis C, Schepers S, Pauwels M, Naert I. Image-based<br />
planning and clinical validation of zygoma and pterygoid implant<br />
placement in patients with severe bone atrophy using customized drill<br />
guides. Preliminary results from a prospective clinical follow-up study.<br />
Int J Oral Maxillofac Surg. 2003 Feb;32(1):7-14.<br />
11. Tardieu P, Vrielinck L. Implantologie Assistée par ordinateur.Cas<br />
clinique: Mise en charge immédiate d’un bridge maxillaire avec des<br />
implants à appuis zygomatiques et ptérygoïdiens. Implantodontie 2002<br />
Août;46:41-8.<br />
12. Tardieu P, Vrielinck L. Implantologie assistée par ordinateur: le<br />
programme SimPlant/SurgiCase et le SAFE System. Mise en charge<br />
immédiate d’un bridge mandibulaire avec des implants transmuqueux.<br />
Implant. 2003;9(1):15-28.<br />
13. Tardieu PB, Vrielinck L, Escolano E. Computer-assisted implant placement.<br />
A case report: treatment of the mandible. Int J Oral Maxillofac Implants.<br />
2003 Jul-Aug;18(4):599-604.<br />
14. Sarment DP, Sukovic P, Clinthorne N. Accuracy of implant placement<br />
with a stereolithographic surgical guide.Int J Oral Maxillofac Implants.<br />
2003 Jul-Aug;18(4):571-7.
Implantology<br />
Comparison of Basal and Crestal Implants<br />
and eir Modus of Application<br />
Dr. Stefan Ihde<br />
Dr.med.dent.<br />
. International lecturer in<br />
implant dentistry<br />
. Editor of “Principles of BOI”<br />
book<br />
. Private practice, Switzerland<br />
dr.ihde@implant.com<br />
36 <strong>Smile</strong> <strong>Dental</strong> Journal Volume 4, Issue 1 - 2009<br />
Abstract<br />
According to the well-known implantological rules for dental restorations, crestal implants<br />
are indicated in situations when an adequate vertical bone supply is given. Crestal implants<br />
function well in patients who provide enough bone when treatment starts, but results are<br />
not predictable as soon as augmentations become part of the treatment plan. Augmentation<br />
procedures are possible today, but they increase the risks and costs of dental implant treatment as<br />
well as the number of necessary operations. Patients providing severely atrophied jaw bones<br />
(i.e. those patients who need the implantologists’ attention most), paradoxically receive little<br />
or no treatment, as long as crestal implants are considered the device of first choice. This article<br />
discusses the value of using basal implants and the differences that exist between basal<br />
implants and crestal implants in perioperative status, infection around integrated implants,<br />
load transmissions and replacement of failing implants.<br />
Keywords: Basal implants, orthopaedic implants, crestal implants, overload osteolysis.<br />
Crestal and basal implants are endosseous aids to create osseointegrated points of retention<br />
for fixed or removable dentures. These two types of implants are not only differentiated by<br />
the way they are inserted and by the way forces are transmitted. Rather, the more substantial<br />
differences lie in the planning and execution of prosthodontic care and, most of all, in the<br />
post-insertion treatment regime. For this reason, the literature on basal implants has introduced<br />
the terms “orthopaedic technique” and “orthopaedic implant” 1 to mark a clear distinction<br />
between them and the well-known term “dental implant”.<br />
Crestal implants (i.e. implants inserted from the top of the alveolar crest into the bone such<br />
as cylinders and blade implants) are indicated in situations where an adequate vertical bone<br />
supply present. Although, crestal implants enjoy a high degree of success, their success is<br />
reduced in cases where bone augmentation procedures become part of the treatment. In<br />
addition, augmentation procedures increase the overall costs of dental implant treatment as<br />
well as the number of necessary operations. Patients providing severely atrophied jaw bones<br />
(i.e. those patients who need the implantologists’ attention most) paradoxically receive little<br />
or no treatment, as long as crestal implants are considered the device of first choice.<br />
Basal implants, i.e. BOI®, Diskos® by contrast, were developed additionally and primarily for<br />
immediate use as well as for use in the atrophied jawbone. They can also be applied where<br />
very little vertical bone is present, while the supply of horizontal bone is still sufficient, even if<br />
these quantities are not contiguous such as in the sinus region. There are no difficult or<br />
impossible cases for implantologists familiar with basal implants, and their use leads in all<br />
cases straight forward to the desired treatment result. The typical objective of treatments<br />
including basal implants is a fixed restoration with 12 teeth per jaw. Optionally, removable<br />
dentures may be inserted as well, as long as enough basal implants are splinted by rigid<br />
connectors (i.e. bars). Single crowns are primarily realized on internal or single-unit BOI<br />
implants. They may be loaded immediately only in favourable situations. As the use of BOI<br />
implants can help avoid risky and expensive bone augmentation procedures, these implants<br />
are the therapy of first choice in moderately or severely atrophied jaws as well as in those<br />
cases, where immediate loading or cheaper treatments are desired by the patients.<br />
Whereas crestal (i.e. axial) implants are inserted vertically from the crest of the alveolar ridge,<br />
basal implants are inserted laterally. These basal implants are synonymously called lateral<br />
implants or disk implants. 2 With basal implants, the regions of load transmission and the<br />
place of bacterial attack do not coincide; no masticatory forces need to be transmitted to the<br />
bone via vertical aspects of the implant; the positive retention in the bone is created in the cortical<br />
bone region.
Differences in Perioperative Status<br />
An implant bed that is congruent with the implant shape is<br />
created using burs for crestal (axial) implants. Most common<br />
crestal implants in use today feature a self-tapping thread,<br />
many types feature compression of bone. Once the crestal<br />
implant is inserted, the insertion site is obturated by the<br />
implant itself. Any infection carried into the implanted bone<br />
intraoperatively or any infection that had already been<br />
present preoperatively (such as residual ostitis) can endanger<br />
the therapeutic result considerably by leading to an early<br />
loss, “idiopathic loss” of implants. The mechanism resulting in<br />
early loss can be described as follows; to combat any such<br />
infection, the flow of blood from and to the bone must be<br />
increased. However, this is inherently inconsistent with the<br />
existence of bone tissue. 3 The resulting increased oxygen<br />
pressure in the bone results in local bone loss, which does<br />
not necessarily involve bacteria or purulence. The implant<br />
loses its stability and will be lost subsequently. The bone<br />
loss associated with this scenario is usually low, since it<br />
barely affects any areas beyond the implant bed itself,<br />
especially if the implant is also rapidly exfoliated. If, however,<br />
exfoliation does not occur as in cases were implants are<br />
kept in place within the bone by the prosthodontic<br />
superstructure, an infection may develop in the spongeous<br />
region that spreads and causes a significant dissolution of<br />
the spongeous and cortical bone substance. In this case, the<br />
cortical bone will be replaced by rapidly formed plexiform<br />
bone, while the bone marrow spaces remain filled with<br />
Migliore Tenuta<br />
Easier Handgrip<br />
Migliore Pulizia<br />
Improved Cleaning<br />
Migliore Comfort<br />
Better Comfort<br />
(Figure 1)<br />
Histological section from a<br />
dog’s mandible, four months<br />
postoperatively. The implant was<br />
inserted in a non-sterile manner and<br />
protected from exfoliation by the<br />
superstructure. The cortical bone<br />
in its entirety was re-formed as<br />
plexiform bone. The implant is not<br />
osseointegrated anywhere.<br />
granulation tissue. The histological findings in such conditions<br />
are typical for an osteomyelitis (Fig. 1).<br />
The situation with basal implants is completely different. For<br />
basal implants, a T-shaped slot is cut into the bone, which<br />
is practically left unobturated by the implant immediately<br />
after insertion. Neither intraoperative nor preoperative<br />
infection will normally threaten the treatment result, since<br />
suppuration from the osteotomy slot is usually uninhibited<br />
at all times. In animal studies, no failure of BOI® implants<br />
(infection of the implant site, primary implant loss, absence<br />
of osseointegration) could be provoked by contamination or<br />
infection present preoperatively or introduced intra-operatively.<br />
The degradation products of infection are resorbed via the<br />
periosteal tissues or removed to the oral cavity through the
Implantology<br />
mucosal access. The necessary pressure is built from inside<br />
the bone. This pressure must never be blocked, and the<br />
direction of flow must never be inverted by the dentist. Early<br />
idiopathic loss thus hardly ever occurs with basal implants.<br />
Infection around Integrated Implants<br />
Crestal (Axial) Implants<br />
Crestal implants are supposed to osseointegrate along the<br />
vertical axis of the implant. The term “osseointegration”<br />
describes a state in which there is no more than an ultra-thin<br />
layer of connective tissue between the implant surface and<br />
the mineralized bone matrix and where this layer contains<br />
neither blood vessels or directional fibres or other components<br />
characteristic of the periodontal system. This is why<br />
osseointegrated crestal implants do not contribute- as<br />
opposed to natural teeth or freshly inserted basal implantsto<br />
draining the bony implant site.<br />
If peri-implantitis develops around crestal implants, the<br />
adducing vessels of the peri-implant mucosa are widened<br />
in a pathological way. In addition, the blood is removed<br />
by the same route it came, requiring space. The resulting<br />
increase in the oxygen pressure in itself causes bone loss.<br />
Whether or not the counteracting tendency towards<br />
retention of the mineralization or towards remineralization<br />
is preserved, will depend on functional stimuli. This is why<br />
crestal implants, if initially osseointegrated, are often lastingly<br />
and stably osseointegrated at their apical even though their<br />
upper enossal portion may be subject to funnel or crater-shaped<br />
areas of bone collapse (Fig. 2). Once the crestal bone is lost,<br />
macrotrajectorial load transmission is shifted to the basal<br />
aspect of the bone, or at least the middle implant region, in<br />
almost all areas of the jaw. Although the total bone mass is<br />
reduced due to the bone collapse, yet the task of transmitting<br />
loads is not made easier as masticatory function persists<br />
and thus the remaining basal bone areas have to be more<br />
strongly mineralized. This will afford them better protection<br />
from further resorption. Nowadays, the surface of crestal<br />
implants is usually enlarged in their enossal part, as they do<br />
not have the retentive baseplates that basal implants have.<br />
The state of the art is that typical surface enlargements are<br />
often created by the manufacturer by adding a TPS layer, by<br />
sandblasting, by etching or by a combination of these latter<br />
procedures. The surface enlargements are to improve the<br />
adhesive properties of the blood and the bone cells,<br />
presumably creating a “cell-friendly” environment. Unfortunately,<br />
bacteria are also cells and a bone-friendly surface is always<br />
at the same time a bacteria-friendly surface. This is why<br />
peri-implantitis around crestal implants is difficult to<br />
control; as soon as surface enlarged portions of the implant<br />
surface are exposed to the oral cavity, these bacteria may<br />
travel more deeply and below the bone level due to the<br />
“candle wick” phenomenon, again increasing blood<br />
circulation and promoting bone loss. As we have seen, only<br />
more highly mineralized bone have better protection<br />
against resorption as a result of the predominant trajectorial<br />
load. This is why some crestal implants have a hybrid<br />
design, where the 1-2 mm of the enossal aspect of the<br />
implants located most closely to the mucosa are not surface<br />
enlarged. However, these implants tend to require more<br />
vertical bone to achieve sufficient retention. More recently,<br />
microsphere-coated surfaces have been introduced in dental<br />
38 <strong>Smile</strong> <strong>Dental</strong> Journal Volume 4, Issue 1 - 2009<br />
implantology, something that has been a familiar concept in<br />
endoprosthetics for quite some time now.<br />
Sintered titanium microspheres, 100–150 µm in diameter<br />
are completely smooth, offering no microretention for bacteria,<br />
even though the surface looks very rough to the naked eye.<br />
Studies have shown that the type and roughness of implant<br />
surfaces determines the behaviour of the osteoblasts.<br />
Osteogenic cells will settle or be created on smooth,<br />
microstructured surfaces more quickly than on SLA surfaces.<br />
The latter show more fibroblastic than osteoblastic cells,<br />
something that ultimately has considerable influence on<br />
implant integration. 4<br />
Basal Implants<br />
With basal implants, load transmission is supposed to<br />
occur primarily, and initially exclusively, within the basal<br />
aspect of the implant, far away from the site of bacterial<br />
infection from the oral cavity. All aspects of the implant<br />
are smoothly polished. Several basal implant systems with<br />
different platforms are available today; internal systems that<br />
can be secured against rotation and that have an internal<br />
screw connection (Fig. 3) and external systems that do not<br />
have a rotation-protected external thread (Fig. 4). With<br />
basal implants, the terms internal and external thus refer<br />
to the thread and not as with crestal implants to the type<br />
and position of the surfaces that protect against rotation.<br />
By design, the mucosal penetration areas are considerably<br />
smaller with external systems than with internal systems.<br />
Whether or not this results in different degrees of resistance<br />
to infection (countable as losses / time unit) has not been<br />
(Figure 2)<br />
Funnel or crater-shaped<br />
crestal bone topography<br />
may occur around<br />
osseointegrated crestal<br />
implants. The extent of<br />
vertical bone loss can<br />
be determined by depth<br />
probing.<br />
(Figure 3)<br />
Internal BOI implants can have<br />
different platforms. Left: An<br />
ITI-compatible Diskos® implant<br />
with octagon. Right: A French<br />
“Diskimplant” with an external<br />
hex. These implants feature all<br />
advantages and disadvantages<br />
of screw implants with internal<br />
connection.<br />
(Figure 4)<br />
One piece external basal<br />
implants for cortical<br />
engagement in vertical<br />
or horizontal bone<br />
morphology.
Implantology<br />
examined. Examining the status of the peri-implant bone<br />
with a probe is considered malpractice with basal implants,<br />
as no osseointegration is required on the vertical aspect of<br />
the implant anyway for permanent function of the implant.<br />
The path of insertion of the vertical aspect of the implants<br />
can no longer be determined postoperatively, and the positions<br />
of the horizontal disk suspensions are unknown. For those<br />
two reasons probing may yield false results. On the other<br />
hand, probing may carry pathogens into the depth of the<br />
interfacial region that is filled with non-irritant connective<br />
tissue at a time when there is little chance of suppuration<br />
left. Callus formation and the maturation of the callus in<br />
the slot areas are endangered through probing. Facultative<br />
pathogens can be transported to an environment that is<br />
normally inaccessible to them and cause great damage. In<br />
particular, the maxillary sinus area may be contaminated<br />
by germs of oral origin by simple probing, if bone height is<br />
reduced or if a trans-sinus implant insertion was performed.<br />
Probing around basal implants is therefore contraindicated<br />
and potentially dangerous. 5 The same considerations show<br />
that rinses and any medication down along the threaded<br />
pins and under pressure are contraindicated. This is because<br />
ahead of the medication, liquid contaminated with pathogens<br />
is pressed into the deep without any control. The direction<br />
of flow is deleteriously inverted, resulting in infectious<br />
osteolysis which is otherwise a rare occurrence. The pressure<br />
of forced medication down along the threaded pins applied<br />
by the treatment provider and his syringe is greater by a<br />
factor than the internal pressure of the bone or soft tissues,<br />
so that this procedure will almost invariably result in massive<br />
adduction of germs and the spread of infection, which may<br />
become chronic. A similar effect is observed if dental restorations<br />
are seated loosely on individual implants for a protracted<br />
time period (months or years) and the continuous relative<br />
movement of the abutment and crown creates a chronic<br />
submucosal inoculation with debris and pathogens. Here<br />
too, inoculation pressure is higher than internal tissue pressure,<br />
resulting in repeated inversion of the direction of flow and<br />
increasing osteolysis due to the measures taken by the<br />
body to fight infections.<br />
With basal implants, there are normally no funnel or cratershaped<br />
areas of bone collapse anyway, as the cortical bone<br />
closes as part of the healing process and no infection<br />
can be transported into the depth of the bone along the<br />
smooth threaded pins. Exceptions may occur if there is<br />
functionally related massive vertical bone growth along<br />
the threaded pin. 6 Surprisingly, bone growth is in some<br />
cases unfavourable, but this is explained by the fact that<br />
bone growth will cause colonized intraoral areas of the implant<br />
to be relocated to submucosal or enossal regions. The<br />
proper therapy in these cases consists invariably in creating<br />
local drainage around the vertical implant part.<br />
With integrated basal implants, infection originating in<br />
the oral cavity would not normally be expected to spread<br />
enossally, for as long as the implants are not mobile to the<br />
extent that they can be intruded. Infections can be caused<br />
by food retention or impaction or as a consequence of vertical<br />
bone growth. However, unlike with crestal implants, they<br />
do not spread intraosseously but submucosally (Fig. 5). The<br />
latter may result in infected vertical parts if the implants are<br />
40 <strong>Smile</strong> <strong>Dental</strong> Journal Volume 4, Issue 1 - 2009<br />
(Figure 5)<br />
With integrated basal implants,<br />
infections unlike crestal implants<br />
do not spread intraosseously but<br />
submucosally.<br />
submerged below the mucosal level over time, eliminating the<br />
necessary gateway for suppuration as the area of penetration<br />
is closed with scar tissue. Any inflammation of this type will<br />
spread just like a submucosal abscess and is treated in the<br />
same way. It is recommended to make generous incisions<br />
to open the abscess. The mucosal area immediately adjacent<br />
to the threaded pin can be excised by electrosurgery. In<br />
rare cases, reduction osteotomies or the replacement of<br />
implants will be required if vertical bone growth becomes<br />
excessive.<br />
Bicortical screws (BCS®) are also considered basal implants,<br />
because they transmit masticatory loads deep into the<br />
bone, usually into the opposite cortical bone, while full<br />
osseointegration along the axis of the implant is not a<br />
prerequisite. BCS provide at least initially some elasticity<br />
and they are not prone to peri-implantitis due to their polished<br />
surface and their thin mucosal penetration diameter.<br />
Peculiarities of Basal Implants<br />
Overload Osteolysis and Basal Implants<br />
It is normally impossible to perform successful recovery<br />
treatment for mobile crestal implants, as the mucosal<br />
penetration area is too large and infections will recur and<br />
descend continuously along the rough interface area.<br />
The situation is different around basal implants; one possible<br />
complication of basal implants, although initially reversible,<br />
is functional overload osteolysis. Successful therapeutic<br />
measures are possible. The physiological background for<br />
overload osteolysis should be however explained briefly;<br />
On one hand, the load-transmitting interface areas are<br />
located in the cortical bone, which has to perform structural<br />
tasks and therefore has a more pronounced self-preservation<br />
tendency, and a more favourable prognosis, than spongious<br />
bone, which is of minor importance both structurally and<br />
with regard to macrotrajectorial tasks and therefore<br />
dispensable. It should be noted, however, that large-lumened<br />
crestal fixtures (just as teeth) are on the way of the jaws<br />
macro-trajectories anyway, so that these bone lines must<br />
seek different paths.<br />
On the other hand, masticatory forces transmitted via the<br />
basal implants to an enossal location create local microcracks<br />
in the cortical bone. 7 Microcracks are repaired by the formation of<br />
secondary osteons, a process called remodelling. This,<br />
however, will temporarily increase the porosity of the<br />
affected bone region and temporarily reduce the degree<br />
of mineralization additionally. If microcracks accumulate
Implantology<br />
at the bone/implant interface, the reduction in mineralization<br />
can also be detected on radiographs (Fig. 6a) where the<br />
osteolytic area initially exhibits only diffuse radiological borders.<br />
As long as the bone substance is not torn away from the<br />
implant (Fig. 6 b) and the area is not superinfected, the loss<br />
of mineralization remains diffuse but usually reversible 8 , and<br />
it should be remembered, that the term “osseointegration”<br />
describes the close contact between bone and the implant,<br />
but it does not describe a high degree of mineralization.<br />
Osseointegration at a lowered degree of mineralization is<br />
not the same as “fibrointegration”. Orthopaedic surgeons<br />
describe the equivalent status of orthopaedic implants as<br />
“sterile loosening”, but they usually have no means of treating<br />
this status. Basal implants in this status have a good chance<br />
of getting reintegrated at a high degree of mineralization,<br />
if loads are reduced to an adequate amount. The measures<br />
necessary are discussed below and they are part of the<br />
education of a basal implantologist.<br />
Radiological findings should be secured both in the form<br />
of overview radiographs (tomographs) and in the form of<br />
summary radiographs (small-format radiographs). The<br />
implant will now be slightly mobile, which is easily discernible<br />
clinically. If areas with mineralization deficiencies are<br />
superinfected, granulation tissue is created in the interfacial<br />
region that will hardly be replaced by new bone without<br />
an added osteotomy stimulus, especially since granulation<br />
tissue requires or results in an increase in blood circulation<br />
that is maintained from a periosteal direction or enossally<br />
and which per se inhibits new bone formation. Nevertheless,<br />
even these implants could be re-integrated in isolated<br />
cases, if the implant site per se exhibits pronounced<br />
remineralization tendencies, for functional reasons. Typical<br />
examples of such areas with pronounced remineralization<br />
are the region of the mandibular second molars, and the<br />
maxillary and mandibular canines (the so-called strategic<br />
positions) and of course the basal regions of the jawbones<br />
as such. These areas must therefore be preferred as implant<br />
sites and other sites outside the strategic regions may even<br />
be dispensed within the case of complete rehabilitation of<br />
an entire jaw, if the concept of strategic implant positioning<br />
is consistently followed. Additional implants may be placed<br />
if the preferred regions offer insufficient anchorage.<br />
An equilibrated masticatory pattern is of particular importance<br />
for maintaining mineralization in the interfacial region,<br />
especially in the first months after implant placement.<br />
Unilateral or anterior (as in Class II division 2 malocclusions)<br />
masticatory patterns result in unilateral or anterior overload,<br />
which would seem to be immediately apparent, and also in<br />
increased porosity of the crestal aspect of the jawbone on<br />
the balancing or distal part of the jaw and thus in atypical<br />
patterns of mineralization. 9,10 This porosity is a consequence<br />
of the increased bone morphological unit (BMU) activity in<br />
this region due to a predominance of tensile forces in this<br />
region. For this reason, mobilization of basal implants can<br />
be expected also on the non-working side on which the<br />
implants are subject to high extrusion forces within the<br />
framework of asymmetrical mastication. In case of mobility, it is<br />
therefore necessary to make adjustments on the side opposite<br />
the mobile side; something that crestal implantologists with<br />
their typical mechanist mindset almost invariably get<br />
42 <strong>Smile</strong> <strong>Dental</strong> Journal Volume 4, Issue 1 - 2009<br />
(Figure 6-a)<br />
Diagram showing a diffuse zone of<br />
low mineralization around the base<br />
plate of a functionally overloaded basal<br />
implant.<br />
(Figure 6-b)<br />
A clearly delimited light zone<br />
on the radiograph is indicative<br />
of an irreversible loosening and<br />
detachment of the bone in the<br />
interfacial region.<br />
wrong. Alternatively, occlusal areas on the underload side<br />
should receive an additive occlusal adjustment, leading to<br />
an equal loading of both sides of the jaw.<br />
Therapeutic Considerations for Overload Osteolysis<br />
First and foremost, the prognosis of the implant must be<br />
determined according to the consensus on basal implants.<br />
As long as implant removal is not indicated11 , there are several<br />
therapeutic strategies that can be followed:<br />
- First of all, it must be determined whether or not the<br />
masticatory pattern is evenly balanced and symmetrical.<br />
If this is not or no longer the case, the first therapeutic<br />
step must be aimed at achieving a bilaterally balanced<br />
situation with regard to bone mineralization tendencies.<br />
- In some cases, extensive occlusal adjustment will therefore<br />
be required. Deficiencies in vertical dimension must be<br />
treated prosthodontically. For example, by building on<br />
the superstructure with composite or by fabricating a<br />
new superstructure with changes in vertical dimension.<br />
The development of anterior masticatory patterns must<br />
be prevented with all means and immediately. Existing<br />
anterior masticatory patterns can usually be corrected by<br />
increasing the vertical dimension; however, the optimum<br />
bite plane must be retained or created and this determines,<br />
in which jaw the addition has to be made.<br />
- Furthermore, the question must be evaluated whether or<br />
not remineralization by way of self-healing or supported<br />
by a suitable therapy can be expected at the existing mobile<br />
implants. 12 Possible therapeutic steps are temporary<br />
isolation of individual implants from the superstructure<br />
and thus facilitating remineralization of the bone<br />
surrounding these implants. The lower bone density<br />
caused by excessive function does not lead to reintegration;<br />
on the contrary, the result will be implant mobility.
Implantology<br />
- If excessive parafunctional habits or nocturnal positional<br />
deviations of the mandible are suspected, the fixed denture<br />
can be replaced, permanently, temporarily or prophylactically,<br />
by a bar-supported denture. 12 This type of denture is<br />
supposed to be removed by patients at night. This will<br />
help avoid peak nocturnal pressure on the bone/implant<br />
interface and result in a very stable direct fixation of the<br />
implants relative to each other. Masticatory shear forces<br />
will also be more favourably distributed between the bar<br />
and the denture.<br />
- It is also possible to add basal implants without removing<br />
mobile basal implants (Fig. 7 a,b). Both implants can<br />
subsequently be integrated with a high degree of<br />
mineralization. The rationale of this procedure is found in<br />
the distribution of the 0 and 1 areas within the bone itself.<br />
Mobile implants create 0-areas at the implant/bone interface,<br />
that is, areas that cannot perform any macrotrajectorial<br />
load transmission tasks. These tasks must then be performed<br />
mostly by bone areas in the vicinity, which will mature to<br />
form highly mineralized 1-areas. However, implantation<br />
into these 1-areas will interrupt the macrotrajectorial load<br />
transmission at the new implant site and promote the<br />
bone’s tendency to once again increase mineralization<br />
around the mobile basal implant. Since the masticatory<br />
forces will subsequently be distributed to two implants,<br />
both implants can stabilize at an even pace. If the dentist<br />
intervenes in time, implant removal can be avoided in this<br />
manner. Additional implants may be required for the only<br />
reason that the masticatory forces can be greatly increased<br />
once the removable denture is replaced by fixed bridges.<br />
This increase in masticatory forces, however, will be<br />
accompanied with an absolute increase in bone mass and<br />
an improvement in bone quality (i.e.degree of mineralization),<br />
something that may have made the insertion of additional<br />
basal implants possible in the first place. Often the placement<br />
of additional Bicortical screws (BCS) implants is easier<br />
than placing more BOI, as BCS implants may be inserted<br />
without a flap procedure.<br />
- If the fixed denture must or should remain in place, the<br />
masticatory forces can be temporarily reduced by injecting<br />
botulinum toxin 13,14 (such as Dysport®) into the masseter<br />
and temporal muscles. This measure also prevents<br />
parafunctional loads and has been clinically proven to be<br />
extremely effective. Botulinum toxin can be administered<br />
prophylactically in cases with a scant bone supply, especially<br />
in the maxilla and especially if bar-retained removable<br />
superstructures are to be avoided right from the start.<br />
Therapeutically, the administration of botulinum toxin is<br />
indicated when BOI implant-supported superstructures<br />
(bone/implant/restoration systems) have become mobile<br />
due to parafunction or due to changes in the bite plane<br />
or masticatory pattern that have remained uncontrolled<br />
for too long. Note that the cause of overloading or missloading<br />
must be treated while the medication is acting.<br />
Otherwise, after the effect of botulinum toxin ceases, the<br />
mobility of the implants will of course return.<br />
- It will frequently be necessary to perform several of the<br />
above measures in combination. At any rate, the correct<br />
44 <strong>Smile</strong> <strong>Dental</strong> Journal Volume 4, Issue 1 - 2009<br />
(Figure 7a-b)<br />
Treating overload-related<br />
osteolysis by adding<br />
a second lateral<br />
implant. Because of the<br />
elastic properties of<br />
these implants, screw<br />
implants must not be<br />
included in wide-span<br />
bridges.<br />
therapeutic decisions must be made well in time and<br />
implemented determinedly, as “self-healing” per se, with<br />
all adverse influences remaining present, can be expected<br />
only in very isolated cases.<br />
The question as to when or for how long the measures<br />
described above may be expected to result in healing or<br />
restabilization at all, cannot be answered summarily. A great<br />
deal of clinical experience with basal implants is required to be<br />
able to make halfway reliable recommendations in borderline<br />
cases. In particular, care must be taken to re-examine the primary<br />
healing process after implant insertion and to check what<br />
types of basal implants were used. In particular the thickness<br />
of the disks, the surface structure of the enossal aspects and the<br />
material properties (i.e. titanium graduation) of the implant in<br />
question, are important factors of treatment planning. Usually,<br />
an untrained secondary treatment provider will not have the<br />
required familiarity with the aspect of masticatory<br />
function and its relation to bone physiology. This alone is<br />
reason enough for complications always to be treated by the<br />
primary treatment provider. If that is not possible when<br />
complications occur, close consultation is required between the<br />
primary and the secondary treatment provider.<br />
BOI implants inserted trans-sinusally without prior augmentation<br />
or lifting of the Schneiderian membrane may cause or<br />
promote sinusitis if there is vertical mobility, usually caused<br />
by overloading. Trans-sinus implant placement with<br />
augmentation (e.g. with Nanos®), by contrast, show a rather<br />
favourable stabilization potential over the medium term.<br />
Primary stabilisation must always be gained in native bone.<br />
Placement of a tubero-pterygoid screw distally of the basal<br />
implant in area six of the upper jaw reduces the chances of<br />
overloading implants in the sinus area dramatically. For this<br />
reason, this type of basal implant should be placed always<br />
in combination with BOIs.<br />
Replacing Basal and Crestal Implants<br />
If an indication for replacing a basal implant really exists,
this measure should be taken right away, since mobile implants<br />
will invariably cause bone damage. By contrast with screw-type<br />
implants, BOI implants will never exfoliate spontaneously.<br />
For this reason and because overload trauma may be<br />
transferred from one side of the jaw to the other via the<br />
denture or via an involuntary change in the preferred working<br />
side, there is no point in waiting. The objective of any<br />
replacement will be to restore the full function of the fixed<br />
restoration and thereby the full range of masticatory<br />
movements. This is why the insertion of the new implant<br />
must be planned along with the removal of the old implant.<br />
In most cases, immediate reimplantation will be possible<br />
and indicated.<br />
When replacing defective implants, the osteotomy for the<br />
new implant must always be created first, that is, before the<br />
existing implant is removed, unless the new implant is to<br />
be inserted in the same position as the old one. It has been<br />
shown that this procedure (i.e. preparing the new osteotomy<br />
before removal of the old implantis), is much easier on the<br />
bone than the inverse procedure; often only very little bone<br />
substance must be removed to remove the old implant.<br />
Leaving isolated integrated implant parts that have no contact<br />
with the oral cavity, in situ, instead of sacrificing a lot of<br />
bone substance to remove them does not usually cause any<br />
problems and can be considered lege artis.<br />
While after the removal of formerly integrated crestal implants,<br />
only rarely new crestal implants can be placed (immediately<br />
or at all), the immediate replacement of (crestal and basal)<br />
implants by basal implants and their immediate loading is<br />
a simple and successful procedure, which is virtually always<br />
possible.<br />
Post-Insertion Treatment of BOI Implants Seen From the<br />
Vantage Point of Crestal Implantology<br />
When complications occur, crestal implantologists unfamiliar<br />
with BOI implants may occasionally argue that there is not<br />
enough bone left for further implant treatment once an<br />
implant is lost. This is incorrect, since there is always enough<br />
available bone in the cranial regions of the facial skull and<br />
the basal region of the mandible.<br />
In practical crestal implantology, saving a case over time<br />
(and beyond the warranty period) is an important aspect. In<br />
the cases of ailing crestal implants that are well<br />
osseointegrated basally but show unavoidable systemrelated<br />
continuous bone loss near the alveolar ridge (Fig.<br />
2), it is possible to sell the patient many years of delaying<br />
peri-implantitis therapy until the situation deteriorates to<br />
the point that leaving the implant in place becomes inconsistent<br />
with any definition of an acceptable oral situation. This kind<br />
of approach is clearly wrong in the case of basal implants.<br />
Problems must be addressed immediately and professionally,<br />
not least in order to prevent the spread of overload-related<br />
damage to other implants, which carries a risk of subsequent<br />
fracture or overload osteolysis and thus to prevent bone
Implantology<br />
loss. It is also not necessary to wait with the corrective<br />
intervention, because every patient has enough bone<br />
for treatment with basal implants. The waiting-strategy of<br />
crestal implantologists is caused with the fear, that after the<br />
removal of the ailing crestal implant no further treatment<br />
with crestal implants is possible. This point of view is<br />
short sighted.<br />
In crestal implantology, specific aspects of masticatory function<br />
play a minor role with regard to bone preservation and<br />
the preservation of the masticatory function per se. Certain<br />
implantological schools traditionally advocate narrow occlusal<br />
surfaces, restricting patients to a primitive chopping<br />
masticatory function. Allegedly, this is done to avoid shear<br />
forces and fractures in ceramics and implant-parts (implant<br />
bodies, screws, abutments); in reality however, the desirable<br />
increased functional stimulation of the jawbone will not<br />
occur. That masticatory function can actually be controlled<br />
to positively influence and modulate the bone/implant<br />
interface. This positive control is usually something that is<br />
beyond the experience of the typical crestal implantologist.<br />
Particularly, serious damage can be observed when and because<br />
a crestal implantologist or a non-implantologist does not<br />
have the possibility (material, knowledge, experience) to insert<br />
additional basal implants, while crestal implants cannot or<br />
must not be inserted due to a lack of vertical bone or due to<br />
their different biomechanical function. A good example is<br />
the extraction of teeth in the opposing jaw or on the contralateral<br />
side, which of course would require the insertion of a fixed<br />
implant-supported replacement restoration in order to<br />
maintain a symmetrical masticatory function. If the patient<br />
is not informed of this or if the treatment is not performed,<br />
the consequence will be overload-related damage on the<br />
working side, either to natural teeth or to implants.<br />
Orthopaedic deformation of the jawbone and the supporting<br />
ligaments and locomotor systems of the cranium as a<br />
result of changes in loads and function, will in turn result<br />
in changes in the relative position of the restorations in the<br />
maxilla and mandible. This will almost always make massive<br />
occlusal adjustments of the restorations necessary over time.<br />
These adjustments must usually be much more pronounced<br />
than the usual experience tells dentists working with crestal<br />
(axial) implants or on natural teeth; orthopaedic deformations<br />
of bones being on the order of millimetres rather than of<br />
microns.<br />
Special consideration when working with basal implants<br />
should always be given to the preservation of a chopping or<br />
a lateral masticatory function: anterior masticatory patterns<br />
must be corrected, which often requires an elevation of the<br />
restoration in the posterior region.<br />
Conclusion<br />
Therapeutic options for peri-implantitis around crestal<br />
implants are limited; usually the disease stops as soon as it<br />
reaches basal (i.e. resorption resistant) bone areas.<br />
Peri-implantitis is not found with basal implants.<br />
For sterile loosening of basal implants, numerous therapeutic<br />
46 <strong>Smile</strong> <strong>Dental</strong> Journal Volume 4, Issue 1 - 2009<br />
options exist; functional adjustments or combined surgical/<br />
functional treatment of bone/implant/restoration systems<br />
are required and in some cases the reduction of muscle<br />
forces is part of the therapy plan. Such options are not<br />
given for crestal implants. Even the replacement or addition<br />
of basal implants is easily possible, since there is usually<br />
sufficient cortical bone available for additive therapy.<br />
Corrective actions must be taken in a timely manner. The<br />
correct diagnosis and treatment of problems related to<br />
basal implants requires specific clinical experience, specific<br />
tools and of course basal implants. This is why the work<br />
with and on basal implants is and has been restricted by the<br />
manufacturer to authorized practioners.<br />
Also with respect to the accepted principle “primum nihil<br />
nocere”, i.e. limiting treatment, basal implants are the<br />
devices of first choice, whenever (unpredictable) augmentations<br />
are part of an alternative treatment plan.<br />
The technique of basal implantology solves all problems<br />
connected with conventional (crestal) implantology. It is a<br />
customer oriented therapy, which meets the demands of<br />
the patients ideally.<br />
References<br />
1 Donsimoni JM, Dohan A, Gabrieleff D, Dohan D. Les implants maxillofaciaux<br />
à plateaux d’assise : troisième partie : reconstructions maxillo-faciales;<br />
Les implants maxillo-faciaux à plateaux d’assise : concepts et technologies<br />
orthopédiques, réhabilitations maxillo-mandibulaires, reconstructions<br />
maxillo-faciales, réhabilitations dentaires partielles, techniques de<br />
réintervention, méta-analyse. Implantodontie 2004 Avril Juin;13(2),71-86.<br />
2 Geman & European Standard: DIN EN 31902-1.<br />
3 Kiaer T. Bone perfusion and oxygenation. Animal experiments and clinical<br />
observations. Acta Orthop Scand Suppl. 1994 Apr;257:1-41.<br />
4 Fillies T, Wiesmann H, Sommer D, Joos U, Meyer U. Primäre<br />
Osteoblastenreaktionen auf SLA-und mikrostrukturierten<br />
Implantatoberflächen. Mund Kiefer GesichtsChir. 2005 Jan;9(1):24-8.<br />
5 Internationnal Implant Foundation. Konsensus zu Sondierungen an<br />
basalen Implantaten. Available at: http://www.implantfoundation.org/<br />
index.php/.Accessed Feb 21, 2009.<br />
6 Ihde S. Adaptations fonctionelles de la hauteur de l’os peri-implantaire<br />
après implantation de BOI dans la mandibule. Implantodontie 2003<br />
Dec;12:23-33.<br />
7 Martin RB, Burr DB, Sharkey NA. Skelettal Tissue Mechanics. <strong>New</strong> York:<br />
Springer; 1998.<br />
8 Ihde S. Principles of BOI., Berlin-Heidelberg: Springer; 2005.<br />
9 Korioth TWP, Hannam AG. Deformation of the human mandible during<br />
simulated tooth clenching. J Dent Res. 1994 Jan;73(1):56-66.<br />
10 Rubin CT, Lanyon LE. Regulation of bone formation by applied dynamic<br />
loads. J Bone Joint Surg AM. 1984 Mar;66(3):397-402.<br />
11 Besch KJ. A consensus on basal osseointegrated implants (BOI).<br />
The Implantoral- Club Germany (ICD). Schweiz Monatsschr Zahnm<br />
1999;109:971-2.<br />
12 Rüedi TP, Murphy WM. AO Principles of bone management. AO Publishing,<br />
Thieme; 2001.<br />
13 Ihde S.Utilisation thérapeutique de la toxine botulique dans le traitement<br />
d’entretien en implantologie dentaire. Implantodontie 2005 Apr-<br />
Jun;14(2):56 -61.<br />
14 Ihde S. Utilisation prophylactique de la toxine botulique en implantologie<br />
dentaire Implantodontie 2005 Apr-Jun;14(2):51-5.
Events<br />
Summary of the Activities of the Arab Society of Oral<br />
Implantology Annual Conference 2009<br />
Cairo, Egypt / 08 - 10 January 2009<br />
The Arab Society of Oral Implantology (ASOI) held this year<br />
a magnificent meeting in Cairo, Egypt, on the 8 th -10 th of January,<br />
2009. The meeting gathered over 670 participants from<br />
Egypt and from all over the Middle East. In this meeting<br />
strong evidence based scientific program and more than<br />
seven different workshops in the various aspects of dental<br />
implantology were presented. Speakers from USA, Austria,<br />
Mexico, Lebanon, England, and Italy gathered for this event.<br />
Parallel sessions for laboratory technicians were also held to<br />
motivate those important element in the dental profession.<br />
The meeting had a final 90-minute-dedicated-panel discussion<br />
between all the speakers and the participants in all the<br />
topics raised during the meeting. A junior podium<br />
competition was also held to elicit the best future dentist<br />
speakers in the field of oral implantology. The competition<br />
was held originally to encourage young dentists to be<br />
on the podium to project their work, ideas, and gain self<br />
confidence. The program had over 21 speakers in the junior<br />
podium this year. Financial and prestigious awards were<br />
given to the top three winners.<br />
“It is the mission of the Arab society of oral implantology<br />
to offer science, modern technology in an affordable and<br />
easy way to all the members of the society” Dr Abdelsalam<br />
Elaskary said.<br />
An up-to date exhibition that gathered over 24 implant<br />
related manufacturers, from all over the world, was held<br />
alongside the conference.<br />
All the scientific events of the Arab Society of Oral<br />
Implantology are fully accredited by the International Congress<br />
of Oral Implantologists (ICOI) and the University of Temple., All<br />
ICOI fellow awardees were awarded in this meeting.<br />
For more information on this meeting, to view a full video<br />
48 <strong>Smile</strong> <strong>Dental</strong> Journal Volume 4, Issue 1 - 2009<br />
Dr. Abdelsalam Elaskary; President of ASOI<br />
Dr. Marco Esposito speaking on evidence based implant dentistry<br />
shooting for this meeting highlights, to check the society latest<br />
educational modules offered, and clinical training courses for<br />
dentists, please log on to www.askaryimplants.com
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VersaWave® Specialty By HOYA ConBio -<br />
Leader in Laser Dentistry- not just precise, it<br />
is precisely the laser you need whether you’re<br />
a general dentist who wants to retain more<br />
challenging procedures or a specialty dentist<br />
who wants to offer superior, gentle results<br />
every referring doctor expects.<br />
The VersaWave® Specialty all-tissue laser is a<br />
versatile and surprisingly affordable addition<br />
to the HOYA ConBio family of dental lasers.<br />
Combining extremely functional VersaWave<br />
technology and user defined features, the<br />
VersaWave Specialty is the laser you want for<br />
the procedures you’ll do.<br />
<strong>New</strong><br />
www.whitesmile.de<br />
www.pirotrading.com
Accutron Inc.<br />
Aurident, Inc.<br />
Vaniman<br />
Micro-Abrasive Blasters For <strong>Dental</strong> laboratory and <strong>Dental</strong> oce oce<br />
SandStorm Expert:<br />
A high quality and economical blasting system for moderate to heavy production. Low<br />
maintenance media flow system virtually eliminates wasteful down-time and lowers<br />
maintenance costs.<br />
Two 50-100 Micron, 1000 ml tanks<br />
• Extra large tanks - Labor saving Easy Fill sand tanks hold up to 4 pounds of media<br />
• Exclusive non-clogging flow design - internal automatic air/media purging system<br />
• Contact-Lens magnified viewing window - reduces eye strain and improves overall viewing area<br />
• Blast proof resin cabinet is maintenance free<br />
• Includes 1 precision Tungsten Carbide Tip plus 1 Crystal Embedded Tip<br />
• Foot pedal control<br />
• Adjustable Air Pressure<br />
• Two hand pieces<br />
SandVac<br />
Dust collection system specifically designed for use with micro-abrasive blasters<br />
• Powerful suction<br />
• Quiet operation (55dbA)<br />
• Compact, space saving design<br />
• Dual function remote control included<br />
• Accumulator pre-filter captures 95% of all dust and 99% of all abrasive media<br />
• Plug in your micro-abrasive blaster and control both with one easy step<br />
• 2 Year Warranty<br />
www.pirotrading.com<br />
Piro Trading introduces Accutron Inc., a<br />
leading manufacturer of<br />
technologically-advanced analgesia<br />
conscious sedation equipment and<br />
accessories. Serving the dental industry<br />
for more than 35 years, the Ultra PC %<br />
Flowmeter is designed for the practitioner<br />
who demands precision control, consistent<br />
performance and state-of-the-art innovation.<br />
The unit combines efficient operation with<br />
optimal safety, and its appearance<br />
complements modern operatory esthetics.<br />
Digital unit is also available!<br />
GO DIGITAL WITH ACCUTRON INC.<br />
<strong>New</strong><br />
www.pirotrading.com<br />
<strong>Dental</strong> Alloys<br />
<strong>New</strong> Products from<br />
Whipmix<br />
Introducing the new Xcavator. the first ever<br />
automated divesting unit for divesting pressable<br />
ceramics. CUT AN HOUR OR MORE FROM YOUR<br />
DIVESTING TIME!<br />
<strong>New</strong><br />
www.pirotrading.com<br />
Aurident provides the Highest quality casting and ceramic alloys to meet all the needs of<br />
the dental technician. For nearly 30 years, Aurident has earned a reputation for<br />
excellence as a manufacturer of a complete line of quality dental alloys for dental<br />
laboratories and dentists worldwide.<br />
Our Identalloy® Council membership assures Aurident customers identifiable, consistent<br />
composition for every package of Aurident alloy.<br />
www.pirotrading.com<br />
<strong>Smile</strong> <strong>Dental</strong> Journal Volume 4, Issue 1 - 2009<br />
57
Flash <strong>New</strong>s<br />
APEX POINTER +<br />
<strong>New</strong> apex locator<br />
Electronic apex locator applying the latest 21 st century high frequency and constant current amplitude<br />
technologies, Apex Pointer+ TM provides accurate, precise and repeatable root canal length<br />
measurements in dry and humid canals.<br />
Advantages<br />
• Easy to operate.<br />
• Rapid: Apex Pointer+ requires no calibration and is ready to use<br />
immediately after self test has elapsed.<br />
• Accurate, reliable and instant measurement whatever the<br />
canal anatomy.<br />
• The measurement is independent of canal conditions – dry,<br />
humid, with blood, saline, hypochlorite, or other liquids.<br />
• Large intuitive liquid crystal display (LCD) indicating gradual<br />
progress of the file, increasing accuracy and resolution when<br />
approaching the apical constriction.<br />
• Stable canal length readings.<br />
• The displayed values are directly related to the file tip location<br />
in the canal and to its distance from the apical constriction<br />
and the apex (foramen).<br />
Vision USA & Piro Trading<br />
<strong>New</strong><br />
Characteristics<br />
• Compact, light weight and wireless.<br />
• Changing beep frequencies to indicate the distance from<br />
apex between the apical constriction and apex.<br />
• Autoclavable electrodes.<br />
• Electronic current limiter guarantees patient’s safety.<br />
• Low power consumption and automatic power off ensures<br />
prolonged battery life.<br />
• Auto test feature.<br />
www.micro-mega.com<br />
Vision USA-a Dentrex Company is pleased to announce that they have appointed Lazar<br />
Piro of Piro Trading International to be their sales and marketing person for the Middle<br />
East and Africa region. Vision USA is extremely excited to offer their products for dentists and<br />
dental laboratories including; Solera High Fusing Porcelain - Shade Perfect Restorations - the<br />
«Injection Precision Cut» grain structure makes Solera the fastest building porcelain available.<br />
Perfect for use with silver containing alloys. It’s non greening with CTE 13.8 - 15.2. Economically<br />
priced, Vision USA Optical - Loupes, Magnification, Safety and Lighting Products to fit all<br />
needs. Vision Lab Supplies - Unique products to enhance production in the dental laboratory<br />
including Purge ZR (Zirconia Decontaminator for your porcelain furnace), Enzo Universal Plaster<br />
less Articulator with disposable bases that can be glued to any model.<br />
Chu’s Aesthetic Gauges<br />
designed by Dr. Stephen J.<br />
Chu, <strong>New</strong> York University, these<br />
Gauges are designed to help<br />
the dentist diagnose tooth size<br />
discrepancies, measure them<br />
accurately and correct them<br />
appropriately.<br />
The Gauges are color-coded<br />
instruments having a<br />
predetermined ratio of about<br />
78%, it is the easiest, fastest, and most precise instruments<br />
for diagnosing tooth size and proportion discrepancies.<br />
They are used to achieve the proper mid-facial clinical<br />
crown and biologic crown length during crown lengthening<br />
procedure and stablish the correct aesthetic position of the<br />
interdental papilla from the incisal edge before the flap<br />
is closed and sutured. Finally, they help to provide quick and<br />
simple analysis of the osseous crest location both mid-facially<br />
and inter-dentally. They are used in aesthetic and surgical<br />
crown lengthening procedure to determine the bone level<br />
before reflecting the flap.<br />
58 <strong>Smile</strong> <strong>Dental</strong> Journal Volume 4, Issue 1 - 2009<br />
www.pirotrading.com<br />
CHOICE 2 Veneers Cement<br />
CHOICE 2 is a high compressive strength, light-cured luting<br />
cement designed for cementation of porcelain and indirect<br />
composite veneers. CHOICE 2 exhibits superior color stability<br />
which is a critical factor in aesthetic veneer cementation<br />
hence eliminating shade shifting, providing exceptional<br />
aesthetics. The material is highly filled and enhances the<br />
overall strength and wear resistance . The film thickness is<br />
ideal to ensure that veneers are successfully placed. Choice 2<br />
is available in a multitude of shades that blend in with the<br />
natural dentition.<br />
www.hu-friedy.com www.bisco.com
EZ-Fill®<br />
Obturation with control. Fill laterally not<br />
beyond the apex!<br />
EZ-Fill’s patented Bi-Directional Spiral and<br />
Epoxy root canal cement combined with a single<br />
point technique has been shown to create a<br />
seal equivalent to lateral condensation and<br />
thermoplastic gutta percha.<br />
• Thoroughly coats the walls of the root canal<br />
and lateral canals without significant cement<br />
being forced apically.<br />
• The reverse spirals on the apical end rotate<br />
in an unwinding direction out of the canal,<br />
and thus never bind.<br />
• Unlike thermoplastic techniques there is no shrinkage<br />
upon cooling.<br />
www.edsdental.com<br />
Angled Bendable Reverse Cone With Adapter<br />
KOS® Implants<br />
4 ways to create angulations in one-piece implants<br />
In the past one-piece implants were used mainly in the posterior<br />
region, because the aesthetic zone often required an angulation<br />
between implant and abutment.<br />
Dr. Ihde <strong>Dental</strong> offers 4 different ways to overcome this problem easily:<br />
- KOS A: implants are available as pre-angulated implants with<br />
a 15 or 25 degree angulation between implant and abutment.<br />
This allows equipping the regions anterior to the maxillary sinus<br />
as well as placement in the (edentulous) front area.<br />
- KOS B: implants provide a bendable neck. The neck is bent<br />
right after insertion. KOS B implants are suitable for circular<br />
bridge and if multiple implants are placed and splinted.<br />
- KOS EB: this reverse cone type features both the aesthetic neck<br />
(4.8mm width) and a reverse cone which allows overcoming<br />
differences in the direction of insertion up to 20 degrees.<br />
- All KOS & KOS A (and BCS): implants may be equipped<br />
with “angulation adapters”. These adapters are cemented or<br />
glued onto the original implant head and help to overcome<br />
differences in the direction of insertion of 15 or 25 degrees.<br />
Implant analogues for these adapters are available.<br />
The KOS concept allows the implantologist to treat virtually all<br />
cases without bone augmentations,- a tremendous advantage<br />
compared to traditional two-piece systems requiring more<br />
width of bone.<br />
KOS implants provide the possibility to work in an immediate<br />
loading protocol.<br />
therese.debs@denterprise-middleast.com
Visit us at<br />
IDS 2009<br />
Hall No. 11.2 P<br />
Stand No. 060
20%<br />
Discount for<br />
<strong>Smile</strong> Journal<br />
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