BISCO DENTAL PRODUCTS CANADA - dentes.sk

COMPOSITE RESTORATIVES
Directed Shrinkage Technique
Introduced first by Dr. Takao Fusayama, and later by Drs. Raymond Bertolotti and John Kanca III, the self-cure posterior
restoration technique known as the “directed contraction shrinkage technique” has provided dentists with a reliable and
efficient means of achieving sensitivity-free restorations for more than 16 years.
This technique suggests that in contrast to light-cured composites, BISFIL II or 2B begins curing adjacent to the naturally
warmer surfaces of the dentin. Since all composites shrink upon polymerization, the net effect of the Directed Shrinkage
Technique is to direct polymerization toward the tooth, improving adaptation to the preparation. In this technique, BISFIL
II or 2B needs to be overlaid with a light-cured composite such as AELITE Aesthetic Enamel.
Bisfil II and 2B are 2 self-cure composites offering 2 viscosities for 2 different placement techniques – pack it or flow it,
the choice is yours.
The contraction forces of self-cure
composites is toward the tooth, maintaining
the adhesive seal of the dentin, eliminating
post-operative sensitivity.
1. In the following case a direct DO composite
resin on the lower left second bicuspid is
placed. The matrix has been placed distally.
The shortened wedge is visible interproximally.
2. With the BiTine-ring in place the matrix
section is stabilized at the same time as the
interproximal space is effectively widened for
a tight contact. The shortened wedge is not
interfering with the ring.
3. UNI-ETCH ® withBAC is a semi-gel
of phosphoric acid with disinfecting
Benzalkonium Chloride used for “total-etch”
bonding. The tooth is etched for 15 seconds
and rinsed with water for 5 seconds. The
surface is left visibly moist, for “wet bonding”.
It is not dried out.
4. ONE-STEP ® / ONE-STEP ® PLUS is the
only single-component adhesive on the
market with full compatibility to chemicallycured
composites. ONE-STEP ® PLUS is the
filled version. The moist tooth is generously
brushed with 2 layers of ONE-STEP ® adhesive.
If a Microbrush, is used, which carries less
adhesive, additional coats must be applied.
5. It is important to air dry correctly so the
adhesive is not blown away. Start drying with
the air syringe at a greater distance. Complete
drying at closer distance. Total drying time is
around 10 sec.
6. A correctly treated surface has typical shiny
“resinous” appearance. If not, additional ONE-
STEP ® coats must be applied.
7. Light-cure ONE-STEP ® for 10 seconds with
a halogen or LED light (with calibrated power
density).
8. With tooth surfaces bonded, the base
increment of BISFIL 2B can be prepared, either
using an automix tip or by handmixing on a
mixing pad. Alternatively, BISFIL II may be
used if a packing technique is preferred.
a
b
9. BISFIL 2B is placed in the deepest part of
the cavity first. The cavity is filled shy of the
proximal contact area. If needed, the material
can be spread out using a probe. It is left to set
for about 2 minutes.
13. With the R.A.P.T.O.R. bur dimples are
placed mesially, distally and centrally indicating
fossae. Fossae are joined so that cuspal planes
and fissures are created. The carbides further
refine the anatomy.
10. Once BISFIL 2B has hardened the rest
of the cavity can be filled with a light-curing
composite of choice e.g. AELITE Aesthetic
Enamel.
14. Following finishing, the surface can be
sealed with FORTIFY or BisCover surface
sealant. The occlusal surface is etched with
UNI-ETCH for 15 sec. Rinsed and carefully
dried with an air syringe.
11. When filling the occlusal part of the cavity,
the unrestricted working time of a light curing
material is valuable for sculpturing.
15. BISCOVER LV is a liquid polish rendering
instant high gloss to the surface, in addition to
sealing it.
12. Finishing and polishing of the restoration
is made easy and fast using the R.A.P.T.O.R. ®
finishing system. With burs a. and b. occlusal
anatomy is shaped. The carbides accentuate
and polish the surface.
16. The etched, rinsed and dried surface is
painted with diluted BisCover LV and cured with
a halogen light for 40 sec.
Dentistry and Photography courtesy of Dr. Johan O. Hultén
1-800-667-8811 / www.biscocanada.com 19