koski1968 BAUME

Cranial growth centers:
Facts or f alla&s?
KALEVI KOSKI, L. OUOXT., 11. ODONT.
Tz~rku,
Finland
T H E term growth center is widely used in connection with skeletal growth
phenomena and thus is also a part of the orthodontic vocabulary.28 Scientific
terms should be clearly defined. However, a brief perusal of the literature reveals
that this term has been used rather loosely to cover many kinds of skeletal
growth site. In fact, the only form of bone growth for which the term has not
been used is the periosteal and endosteal growth, with the modeling resorption
linked with it.
In the second Mershon Memorial Lecture, Baume? proposed that the term
skeletal growth center be used to describe “places of endochondral ossification
with tissue separation force.” It seems that this very idea is implicit in most
usages of the term growth center. If the definition is accepted, then it seems
that the epiphyseal growth plate (Fig. 1) is the prototype of the growth
center.131 24145147148s 84 One has only to read a few discussions on cranial growth to
see that most authors agree with this, since they compare the various cranial
“growth centers,” whatever they may be, with the epiphyseal growth plates.
The definition proposed by Baume already implies a degree of spatial limitation,
that is, a growth center includes only the territory where endochondral
ossification is taking place. The time element also appears important. Some
sites of endochondral ossification are of a very temporary nature only and do
not contribute to the growth of the skeleton in an appreciable way (for example,
the secondary ossification centers of the epiphyses). Thus, the term growth
center should mean a place where growth of the skeleton is occurring for a sufficient
length of time to make a real contribution to the increase of the skeletal
mass beyond t,he size of the model tissue existing at the onset of the growth center
function. A modified definition, therefore, would be that a growth center is a
site of endochondral ossification with tissue-separating force, contributing to the
increase of skeletal mass.
566
Presented as the John V. Mershon Memorial Lecture at the annual meeting of the
American Association of Orthodontists in St. Louis, MO., April 23, 1967.

Cranial growth centers 567
Fig. 1. A well-organized epiphyseal growth plate in a transplant originally consisting of the
distal cartilaginous end of the radius of the rat, after a 39.day period of transplantation
in the brain tissue.
In the following review I shall try to examine some of the alleged growth
centers of the craniofacial skeleton, using this definition as the criterion. In
order to be more meaningful from the orthodontic point of view, the discussion
will be limited to the postnatal period.
SUTURES
On the basis of the definition, the sutures cannot be called growth centers.
Baume? proposed the term growth site for “regions of periosteal or sutural bone
formation and modeling resorption adaptive to environmental influences,” a
definition which has been accepted by a recent textbook of orthodonticsT1 As
will be seen later, there is much evidence in favor of this differentiation between
growth centers and growth sites. However, since sutures have been called growth
centers or have been regarded as being homologous to epiphyseal growth
plates,4gs *o-83, Q” the “case of the sutural growth” must be dealt with here in some
detail. For a rather comprehensive discussion of this problem and of the cranial
growth in general, a recent review by Hoyte31 is recommended.
That a considerable amount of growth occurs in the sutural areas has been
proved by many authors,% 2% 49, 51, 52, 62, QL 92 and from that point of view the
so-called sutural growth is of major importance in craniofacial growth.
There appear to be two differing views concerning the structure of the
sutures (Fig. 2).

5 68 Koski
Fig. 2. A schematic illustration of the two &Bering views on the structure of the suture. A
represents the three-layer concept; B, the five-layer concept (see text).
B
One school of thoughP+ go sees the suture as a. three-layer structure. It maintains
that the connective tissue between the two bones plays the same part as
the cartilage at the base of the skull, in the epiphyses, and on t,he articular
surfaees of long bones, that is, there is n “spreading” of the suture, initiated by
the proliferation of the middle layer cdls of the sutural tissue. This concept
appears to imply the existence of “tissue-separating force” in the sutural tissue.
The other concept regards the suture as a five-la.yer structure.62, *O, 81 Each
bone at the suture has its own two-layer periosteum covering also the opposing
surfaces of the bones as if the bones were in a package, and there is a fifth layer
between these periosteal layers. The role of this fifth layer is seen in allowing
for slight adjustments between the bones during growth, while the active proliferating
role is played by the cambial layers of the periosteums of each
bone 26, 51, 62, 75
When histologic specimens of sutures are examined, it is obvious that men
of both schools of thought must have studied the same structures, and they
differ only in the interpretation of the structures (Fig. 3).
It may be mentioned in passing that cartilage tissue has been observed in
the suture areas,54l 62 but it has not been found to be of significance as a growth
center; in some instances, it appears at t.he time of the closure of the suture.54
It is quite clear that the structure of a suture is not at all similar to that of
an epiphyseal growth plate. The question remains: is there an expansive force?
Is the growth in the sutural area of primary nature, that is, does it have an
independent growth-promoting potential, thereby pushing the bones apart, or
is it of secondary nature, a response to some factor or factors, primarily effecting
the separation of the bones and thus necessitating or allowing for an apposition
at the bone surfaces ? (Fig. 4.)
Some authors maintain that “there is no doubt that sutural growth is a
primary and active mechanism for the enlargement of the cranium” and that

Volume 54
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Cranial growth centers 5 69
Fig. 3. A photomicrograph of a section of the intern-1 suture of the rat. Note that the
periosteum appears to be continuous all around the bone edges, with a vascular layer between
the periosteal layers in the suture itself.
“the apposition of new bone at the sutural surfaces enlarges the single bones
but not the cranium.“s3 This concept is challenged by others, who maintain that
the sutures are not acting as primary growth agents56-5sy 75~ 77 but that the growth
in the sutural areas is secondary and caused by the growth of cartilaginous elements
of the craniofacial complex75y 77 or by the effect of the so-called “functional
matrix.“56l 58
Obviously, these differing opinions are not necessarily correlated with the
different views of the functional structure of the sutures. Whether the appositional
growth at the bone edges in the sutural areas is regarded as being due
primarily to the proliferation of the middle layer cells or of the cambial layer
cells, it may still be either a relatively independent growth process or governed
by some external forces.
Evidence in favor of the dependent role of the sutural growth appears to
be accumulating.
The literature contains only a few observations that are directly related to
this problem. It has been observed that the trabecular pattern in the bones at
the sutures changes with age, probably indicating the changes in the direction
of growth,34 and it is difficult to believe that the sutural tissue itself would have
the information necessary for altering the direction of growth. Subcutaneous
autotransplants of the zygomaticomaxillary suture area in the guinea pig have

* k
Fig. 4. A schematic illustration of the two differing views on the function of the suture. B
represents the concept of a thrusting force residing in the sutural tissue itself; B represents
the concept of an outside force separating the bones from each other.
Fig. 5. A schematic illustration of the nearly parallel superficial direction of the main sutures
of the upper face and of the range of direction of maxillary growth. (After BjGrk: Aota
odont. scandinav. 24: 109-127, 1966.)
not been found to grow,sg which clearly speaks against the existence of an autonomous
growth potential in the sutural tissue. An extirpation of facial sutures
appears to have no appreciable effect on the dimensional growth of the skeleton.73
The shape of the sutures has been found to depend on functional stimuli,53x 57 the
closure of the sutures appears likewise extrinsically determined,54 the sites of
sutures appear not to be predetermined,27 and it is possible to bring the sutural
growth to a halt by such mechanical forces as metal clips applied across the
suture@ or even by inserting a solid bone bridge in the suture.26 In a recent
study in which defects in fibulas of rabbits and dogs were filled with autotransplants
of cranial sutural areas, it was found that the sutural tissues grew so as
to maintain the normal increase in length of the bone.66 This certainly demonstrates
the great adaptability of the sutural tissue, but it does not prove that
the tissue has an independent growth potential.
A popular view holds that the circum-maxillary sutures are parallel to each
other so as to effect the forward-downward growth of the maxilla.8sr 9o However,
it has been shown that this parallelism is only superficial ; the growth at the
zygomaticomaxillary suture, for instance, occurs mainly in a lateral direction.”

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Cranial growth centers 571
Fig. 6. A photomicrograph of the basi-presphenoid synchondrosis of the rat showing the
resemblance of this cartilage to an epiphyseal growth plate.
Furthermore, the direction of growth of the maxilla may vary from 0 to 82 degrees
in relation to the sella-nasion lineI (Fig. 5). How would the sutures,
which are running in practically the same direction in every face, know when to
push the maxilla parallel to the reference line and when to push the jaw in an
almost straight downward direction ?
From the evidence presented, one comes to the conclusion that it is unlikely
that the sutural tissues have a tissue-separating force and that they are not,
therefore, even comparable to growth centers.
CRANIAL BASE SYNCHONDROSES
The importance of the synchondroses of the cranial base, especially of the
spheno-occipital synchondrosis, is stressed almost universally,4p ‘1 s* 71r 75, 78, Tsg *2*
a37 w 9o and most authors regard it as a growth center of primary value for the
growth of the craniofacial skeleton.
There is no doubt about the structural similarity between the basicranial
synchondroses and the epiphyseal growth plates, although some minor differences
in histology and histochemistry seem to exist between these two categories
of cartilage70 (Fig. 6). The reaction of the synchondroses to various biochemical
stimuli is also similar to that of the epiphyseal growth plates73 32s 69
and it is obvious that endochondral ossification is taking place adjacent to these
cartilages. The scene appears to be ready for the title of growth center-but
is it?
Actually, there appears to be no published evidence of the existence of a
tissue-separating force in the synchondroses. The removal of the spheno-occipital
synchondrosis has been observed to result in an arrest of growth in length of
the cranial base,lg but this does not prove that the cartilage has an independent
growth-promoting potential. The considerable amount of growth that occurs in

Fig. 7. No growth is evident in :I 304:1y t r:tt~s~)lantntiorl (subcut,aneous) of a cranial base
synchondrosis of the rat.
the cranial base, probably due mostly to the endochondral ossification at the
synchondroses, may still be only a response to external stimuli4”
One way of trying to obt,ain direct information about the independent
growth potential of this cartilage is to follow its growth as a transplant in a
relatively nonfunctional site. 24 When this is done, it is seen tha.t the basieranial
synchondroses do not grow and effect dimensional growth of the adjacent bone4G
in a manner comparable to that seen in situ4 (Fig. 7). The cartilage appears
not to have the same amount of independent, growth potential as t,hat observed
in transplants of epiphyseal cartilage under similar experimental condi-
tions 24, 45, 47, 48, 89
In this connection, it should be mentioned that some authors have expressed
doubt about the significance of the spheno-occipital synchondrosis for cranial
growth, on the basis that it appears to close much earlier than is usually stated
in the textbooks, namely, when the individual is 11 to 16 years of age,O1 and
that, even until that time, the dimensional increase of the clivus during the
postnatal period is very slight.”
It appears, then, that at the present time there is no direct evidence to
support the claim that the synchondroses are growth cent,ers in the sense of the
definition.
CARTILAGE OF THE NASAL SEPTUM
The role of the cartilaginous nasal septum has been discussed by many authors
also ‘9 ‘3 7l I43 ‘j, 78, 7o, 80, 81 and the general consensus seems to he that it pro-
,

Cranial growth centers 573
A
Fig. 8. Schematic illustration of the cartilaginous nasal septum, of its relation to the neighboring
structures, ad of its alleged growth directions. A, Sagittal view; B, frontal view.
E, Ethmoid bone; M, maxilla; S, septum; V, vomer.
B
Fig. 9. A photomicrograph of the posterior part of the cartilaginous nasal septum of a young
rat, in which two areas of endochondral growth show. (Courtesy of Dr. 0. RBnning.)
vides a thrusting force which carries the maxilla forward and downward during
growth (F’ig. 8). Could it be a growth center?
Histologic examinations reveal that there is endochondral ossification taking
place at the septo-ethmoidal junction6 and that there is an area of proliferation
at the vomeral edge of the cartilage7 (Fig. 9). In the palatal area there is resorption
on the nasal side and apposition on the oral side of the bony
palate.2l 7, *L 22 These findings appear to support the general opinion.
Experimentally, it has been shown that excision of the nasal septum affects
the growth of the upper face considerably. 73y 74 However, it is clear that these
experiments do not prove anything about the role of the nasal septum; they
show only what happens if it is not there, and the malformations resulting from

the operations may dust as well b(: ,Iuc~ to t t~;~um;l.l~ I1 is ills0 cYJ~llCY~iVillblP t Il;tt till’
nasal Sf?~1tUlll is a central SUpport fol’ tllt& ll])[K’? f;lc+al ill'f'il. iUltl ils loss II~SIlLtS
in a predictable co1 lapse in thtl ar(‘i~.
An early submucous resection of tht, rlasal septum clot3 not s(‘om to ha\,(h an>
adverse effect. on the devclopmcnt of th(l middle fa(~.“; A twcnt wpnrt (‘oneerning
an arrhinencephalic Cl-month-old child (with the septum missing) states
that the resorption and apposition ~I’OWSWS in the hn,v I)aliit,c WPIY’ occurring
normally and that the height of the nppcr face was not greatly aR’ccted, although
the sagittal development of tht nlitldle third of the fact was rt~tardctl.“”
This finding seems t,o indicate that the nasal cartilaginous scptnm may be im
portant for the anteroposterior growth 0-l’ the upper face, prcsuma.blp hccanse of
the endochondral growth process occurring at its posterior horder! but that it
is not an active contributor to the verticaal dcvclopment of the fact.
On the basis of the present evidence, wc may conclude that the septo-ethmoidal
junction possibly acts as a growth center during postnatal life, although
direct evidence of this is lacking and may. indeed, be difficult, to obtain.
CONDYLAR
CARTILAGE
The cartilage in the condyle of the mandible has probably been subject to
more studies and discussions than any other part of the cra,niofacial skeleton,
from the stand-point of growth.
Most orthodontic texts seem to accept the opinion that “growt,h at the
condyle moves the mandibular body forward and downward and thus opens the
space below the cranial base int,o which mandibular and maxillary alveolar
processes grow and teeth erupt,” and the eondylar growth is, therefore, considered
“indispensable for the normal vertical growth of the face.“‘” It has also
been claimed that the growth of t,he condylar cartilage is responsible for the
anteroposterior growth of the mandible,” and the general feeling seems to br
that we are here dealing with the most important growth center of the lower
jaw.‘3
There have been a few claims to the contrary. Scott7” wa.s of the opinion that
the growth of the condylar cartilage enables the condylr “to grow upwards and
backwards so as to maintain the contact at the temporomandibular joint as the
mandible is carried downwards and forwards by the growth of the upper facial
skeleton.” He further compared the condyle to the end of the clavicle, maintaining
that they are similar in structure, and pointing out that it would not
be correct to say that the clavicles are pushing the sternum and scapulas apart.
During the past few years, MOE@, X+ 5x has been advocating the same view as far
as the role of condylar growth is concerned, but he maintains that the governing
agent is the so-called “functional matrix.”
The structure of this cartilage has been studied and explained by many authors.7,
12, =, 85y se3 9o Apparently, however, the findings of researchers have often
been misinterpreted by readers who have not had first-hand knowledge of the
subject, and a few remarks seem to be called for after all.
This cartilage is a latecomer, a secondary cartilage, and not a part of the
Meckel’s cartilage that acts as the model for the early development of the man-

Volume 54
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Cranial growth centers 575
Fig. 10. The condyle of a Sday-old rat. There is a relatively wide intermediate layer (the
upper third of the nonossified top of the condyle, excluding the narrow darkly stained articular
zone), a narrow zone of cartilage cells, and a wide zone of hypertrophic cells (darkly
stained). Note the absence of a structural organization, as seen in the epiphyseal growth
plate in Fig. 1. (Courtesy of Dr. 0. Ronning.)
dible. It is not an articular cartilage, nor is it an epiphyseal growth plate
(Fig. 10). It does not even form from the same embryonic precursor tissue as
the epiphyseal cartilages,53 36 a fact which may have something to do with its
structure and function.
It is claimed that the condylar cartilage grows not interstitially, like the
epiphyseal cartilages, but appositionally from the deepest layer of the connective
tissue cover of the condyle.82~ 83185l 86p 9o Th’ is mitotic layer responsible for the
increase of the cartilage is also called the intermediate layer. It is located between
the surface of the condyle and the cartilaginous portion of it,12 and the
cells of this layer are not cartilage cells but are rather like undifferentiated
mesenchymal cells.7o In the epiphyseal cartilages, as we know, the proliferating
cells are cartilage cells. There are other differences between the condylar cartilage
and the epiphyseal growth cartilages. The structural organization present
in the epiphyseal growth apparatuses is lacking in the condylar cartilage, and
the zone of nonhypertrophic cartilage cells in the condyle is very narrow, the
forming cartilage cells turning hypertrophic almost immediately,12> 7o as in the
clavic1e.l It is of special interest that the whole hypertrophic area in the condylar
cartilage seems to be in a state of mineralization, whereas in the epiphy-

576 Koski
Fig. 11. Two subcutaneous transplants of thr c~~ndplar wrl ilag~: proper, originally from a
3.day-old rat, after 30 days of transplantal ion. Both spwimws aw ljartly raytilaginous, but
chondroid bone formation is also soen, oq~wially in the larger qwcirncbn. Thv smaller one is
of the original size, and the larger ant> appcaw lo Imw incwnswl in sizc in :i direction corresponding
to the sagit,tal dimension in sit,,.
Fig.
from
condj
12. A subcutaneous transplant of the condylar cartilage plus
a 5-day-old rat, after 30 days of transplantation. There is a m
de in situ.
adjacent ossified r amus
oderate resemblance to a

Volume 54
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Cranial growth centers 577
seal growth apparatuses only the degenerative zone is mineralizing.70 Finally,
the so-called primary spongiosa, always present in the long bones, seems to be
absent in the condyle.33a TO
In regard to the function of the condylar cartilage, differences have been
found to exist between it and the epiphyses. The condylar cartilage is highly
responsive to mechanical stimuli79 8a I51 I6 and responds differently from the epiphyseal
cartilages to various hormonal and chemical agents.?’ 32~ 6g
The decisive point is the question of the tissue-separating force or the independent
growth-promoting potential. As mentioned earlier, the existence of this
force or potential has been implicit in the interpretation of the function of the
condylar cartilage in most descriptions of the condyle. This problem can again
be tackled by way of transplantation. If the condylar cartilage is transplanted
to a relatively nonfunctional site, such as the subcutaneous or brain tissue, it
does not maintain its structure and does not behave like the condylar cartilage
in sit@+ 68 (Fig. 11). Only when it is accompanied by a piece of adjacent
bony ramus may the transplant grow, and even then the structure is not maintained
in the beautiful manner observed in transplanted epiphyseal cartilages249
45847348 (Fig. 12). Tissue-culture studies have also demonstrated lack of
growth of the condylar cartilage.6o
Thus, these experiments have furnished evidence for the lack of growth
potential in the condylar cartilage, and the condylar cartilage does not seem
to fulfill the definition of a growth center.
Actually, the opinion that the condylar cartilage and its growth would be
of major importance for the growth of the mandible, let alone the face as a
whole, appears rather odd, considering the known facts. To a la,rge extent, the
mandible grows in size by periosteal and endosteal apposition and remodeling
resorption.14* 2os 64p *Or Q 83~ 9o Furthermore, it seems obvious t.hat this bone consists
of several relatively independent parts, whose existence and growth depend on
different factors39 2gg 85 These facts already speak strongly against the simple idea
that the growth of the mandible would be dependent on growth at the condyle,
located in one corner of the curved bone.
There is a great deal of further clinical and experimental evidence against
Fig. 13. A schematic illustration of the effect of a condylar resection in monkey (based on
Sarnat’s illustrations). The black point represents the mental foramen, which has been used
as the point of superimposition; the alveolar margins have also been superimposed.

578 Koski
the idea that the condylar cartilage is of major importance Sor the growth of
the mandible. Bilateral condylectomy,“” even the congenital absence of the
rami, has been found to have no appreciable effect on the growth of the rest
of the mandible in human patients, and the same finding has been made in
connection with experimental condylectomies in animalsl”s 25, K 72 The fact that
the mandibular growth may result in deformation after condylectomy, especially
in the posterior part of the ramus, cannot be used to support the idea of the
condyle’s important role, since the deformation is to be expected (Fig. 13).
The cartilage in the condyle provides for some growth of the posterior part of
the ramus and, if this provision is lacking, then the mandible, in its own field
of muscular and other forces, is bound to grow abnormally.
The claim that the condylar growth directs the growth of the mandible
appears to be incorrect. It is known that the direction of the condylar growth
may vary considerably. 63 This is especially well demonstrated b.y studies involving
the use of metallic implants, which show that the act,ual growth of the
condyle is sometimes upward and backward and sometimes upward and forwardlo
(Figs. 14 and 15). It is very hard to imagine how, in the latter cases,
the condylar growth would be able to propel the mandible forward and downward.
The information available on condylar growth appears very strongly to

Volume 54
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Cranial growth centers 579
Fig. 15. The outlines of the three mandibles shown in Fig. 14 superimposed on the condyle.
Compare the apparent growth direction as viewed from the temporomandibular joint with the
actual one shown in Fig. 14. The discrepancy between the findings cannot be explained by the
concept of the eondylar cartilage having a pushing and directing force,
point toward its subordinate role as a site of growth, not as a growth center, in
the growth of the mandible.
CONCLUSIONS
The foregoing discussion of the available information concerning the growth
of the craniofaeial skeleton has led to the conclusion that most of the areas
which have been labeled growth centers in the past either do not qualify as such
or have not been studied sufficiently for the claim to be proved beyond doubt.
If these sutures and cartilages do, indeed, lack independent growth-promoting
potential, what are the factors responsible for the craniofacial skeleton?
Several students of craniofacial growth have proposed essentially similar
concepts regarding it. Van der Klaauw3g viewed the skull as composed of more
than thirty relatively independent functional units, each governed by its own
functional growth director, as it were. Scott16 divided the craniofacial skeleton
into eight different regions, each having its own growth pattern, related to the
different organs they house or support. The latest theory is presented by Mos+~,~~* s8
who maintains that the growth of the craniofacial skeleton is under the influence
of the “functional matrix,” by which he means all the soft tissues (even empty
spaces) within which the bony structures are embedded.

Thcrc is, as TW have seen, much c~vitlence, both clinical and experimental,
that can be used to support these theories.“’ SO. li5f RS, w The t hcorics, howr’vt~r’, arc
not explicit enough, it seems, and they ha\e not, been prowd beyond an?- doubt.
Nerertheless, they appear valuable as stimuli and as l\orking hppothwrs for
further research in the field. Rincc so many observations apptlar Incompatible
with older views, we should keep an opw mind and look I’or c~xplanations and
theories that would be in agreement with all the known facts.
The author’s own research reported here has been supported by grants from The Sigrid
Juselius Foundation, Helsinki, Finland, and from the National Inst,itutes of Dcmtal Research
(Dl434, DE-01793) and of Child Health am1 Human Development (HI)-001 771, United
States Public Health Service.
REFERENCES
1. Andersen, H.: Histochemistry and Development of the Human Shoulder and Acromioclavicular
Joints With Particular Refcrenre to the Early Development of the Clavicle,
Aeta Anat. 55: 124-165, 1963.
2. Applrbaum, E.: Integration of Anatomic and Cephalometric Studies of Growth of the
Head, A&f. J. ORTHOIMZNTIC~ 39: 6’12-622, 1953.
3. Bvis, V.: The Significance of the Angle of the Mandible: An Experimental and Comparative
Study, Am. J. Phys. Anthrop. 19: 55-61, 1961.
4. Baer, M. J.: Patterns of Growth of the Skull as Revcalod by Vital Staining, Hurrmn Biol.
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5. Balinsky, B. I.: An Introduction to Embryology, Philadelphia, 1960, W. B. Saunders Co.
6. Baume, L. J.: The Postnatal Growth Activity of the Nasal Cartilage Septum, Helvet.
odont. acta 5: 9-13, 1961.
7. Baume, L. J. : Principles of Cephalofacial Development Revealed by Experiment,al Biology,
AM. J. ORTIIOD~NTICS 47: 881-901, 1961.
8. Baume, L. J., and Derichsweiler, H.: Is the Condylar Growth Center Responsive to
Orthodontic Treatment B Oral Surg., Oral Med. & Oral Path. 14: 347-362, 1961.
9. Bjark, A. : Cranial Base Development, AM. J. ORTHODONTICS 41: 198-225, 1955.
10. Bjb;rk, A.: Variations in the Growth Pattern of the Human Mandible: Longitudinal
Radiographic Study by the Implant Method, J. D. Res. 42: 400-411, 1963.
11. Bjb;rk, A.: Sutural Growth of the Upper Face Studied by the Implant Method, Acta
odont. scandinav. 24: 109-127, 1966.
12. Blackwood, H. J. J.: Growth of the Mandibular Condyle of the Rat Studied With
Tritiated Thymidinc, Arch. Oral Biol. 11: 493-500, 1966.
13. Blount, W. B., and Clarke, G. R,.: Control of Bone Growth by Epiphyseal Stapling, J.
Bone & Joint Surg. 31A: 464-478, 1949.
14. Brash, J. C., McKeag, H. T. il., and Scott, J. H.: The Aetiology of Irregularity and
Malocclusion of the Teeth, ed. 2, London, 1956, The Dental Board of the United Kingdom.
15. Breitner, C.: Bone Changes Resulting From Experimental Orthodontic Treatment, AM. .J.
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Orthodontic Treatment, AM. J. ORTHODO~ICS & ORAL SURG. 27: 605-632, 1941.
17. Coulombre, A. J., and Crelin, E. 8.: The Role of the Developing Eye in the Morphogenesis
of the Avian Skull, Am. J. Phys. Anthrop. 16: 25.37, 1958.
18. Das, A., Meyer, J., and Sicher, H.: X-ray and Alizarin Studies on the Effect of Bilateral
Condylectomy in the Rat, Angle Orthodontist 3.5: 138.148, 1965.
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An Experiment in Growth and Form, Am. J. Anat. 109: 117-132, 1961.
20. Enlow, D. H., and Harris, D. B.: A Study of the Postnatal Growth of the Human
Mandible, AM. J. ORTHODONTICS 50: 25-50, 1964.

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Cranial growth centers 581
21. E&w, D. H., and Bang, S.: Growth and Remodeling of the Human Maxilla, AM. J.
ORTHODONTICS 51: 446-464, 1965.
22. Enlow, D. H.: A Morphogenetic Analysis of Facial Growth, &M. J. ORTHODONTICS 52:
283-299, 1966.
23. Enlow, D. H., and Hunter, W. S.: A Differential Analysis of Sutural and Remodeling
GrowthintheHuman Face, AM.J.ORTHOD~NTICS 52: 823-830,1966.
24. Felts, W. J. L.: In Vivo Implantation as a Technique in Skeletal Biology, Int. Rev. Cytol.
12: 243-302, 1961.
25. Gianelly, A. A., and Moorrees, C.F.A.: Condylectomy in the Rat, Arch. Oral Biol. 10:
101-106, 1965.
26. Giblin, N., and Alley, A.: Studies in Skull Growth. Coronal Suture Fixation, Anat. Rec.
88: 143-153, 1944.
27. Girgis, F. CT., and Pritchard, J. J.: Effects of Skull Damage on the Development of
Sutural Patterns in the Rat. J. Anat. 92: 39-51, 1958.
28. Graber, T. M.: Orthodontics-Principles and Practice, ed. 2, Philadelphia, 1966, W. B.
Saunders Co.
29. Horowitz, S. L., and Shapiro, H. H.: Modifications of Mandibular Architecture Following
Removal of Temporalis Muscle in the Rat, J. D. Res. 30: 276-286, 1951.
30. Horowitz, S. L., and Shapiro, H. H.: Modification of Skull and Jaw Architecture Following
Removal of the Masseter Muscle in the Rat, Am. J. Phys. Anthrop. 13: 301-308, 1955.
31. Hoyte, D. A. N.: Experimental Investigations of Skull Morphology and Growth, Internat.
Rev. Gen. & Exper. 2001. 2: 345-407, 1966.
32. Irving, J. T, and Riinning, 0. V.: The Selective Action of Papain on Calcification Sites,
Arch. Oral Biol. 7: 357-363, 1962.
33. Irving, J. T., and Durkin, J. F.: A Comparison of the Changes in the Mandibular Condyle
With Those in the Upper Tibia1 Epiphysis During the Onset and Healing of Scurvy,
Arch. Oral Biol. 10: 179-185, 1965.
34. Isotupa, K., Koski, K., and Makinen, L.: Changing Architecture of Growing Cranial
Bones at Sutures as Revealed by Vital Staining With Alizarin Red S in the Rabbit, Am.
J. Phys. Anthrop. 23: 19-22, 1965.
35. Jarabak, J. R., and Thompson, J. R.: Cephalometric Appraisal of the Cranium and
Mandible of the Rat Following Condylar Resection, J. D. Res. 28: 655656, 1949.
36. Johnston, M. C.: A Radioautographic Study of the Migration and Fate of Cranial Neural
Crest Cells in the Chick Embryo, Anat. Rec. 156: 143-156, 1966.
37. Kazanjian, V. H.: Bilateral Absence of the Ascending Rami of the Mandible, Brit. J.
Plast. Surg. 9: 77-82, 1956.
38. Kivimiiki, J.: Leukanivelankyloosista, Suomen Hammaslaak. Toim. 63: 15-18, 1967.
39. Van der Klaauw, C. J.: Cerebral Skull and Facial Skull. A Contribution to the Knowledge
of Skull-Structure, Arch. Neerl. 2001. 7: 16-37, 1945.
40. Koski, K.: Some Aspects of the Growth of the Cranial Base and the Upper Face, Odont.
Tidskr. 68: 344-358, 1960.
41. Koski, K., and Iv&kinen, L.: Growth Potential of Transplanted Components of the
Mandibular Ramus of the Rat. I., Suomen Hammaslaak. Toim. 59: 296-308, 1963.
42. Koski, K., and Mason, K. E.: Growth Potential of Transplanted Components of the
Mandibular Ramus of the Rat. II., Suomen Hammasl%k. Toim. 60: 209-217, 1964.
43. Kosski, K.: Growth Potential of the Mandibular Condyle in the Light of Transplantation
Studies, Studieweek 1965: 35-45, 1965.
44. Koski, K., and RSnning, 0.: Growth Potential of Transplanted Components of the
Mandibular Ramus of the Rat. III., Suomen Hammasltik. Toim. 61: 292-297, 1965.
45. Koski, K., and Riinning, 0.: Pitkan luun rustoisen p&r siirriinnaisen kasvupotentiaalista
rotalla, Suomen Hammasltik. Toim. 62: X5-169, 1966.
46. Koski, K., and RSnning, 0.: Growth Potential of Transplanted Components of the Cranial
Base of the Rat. To be published.
47. Koskinen, L., and Koski, K.: Regeneration in Transplanted Epiphysectomized Humeri
of Rats, Am. J. Phys. Anthrop. 27: 33-40, 1967.

582 Koski
48. Lacroix, I’.: The Organization of Bones, .London, 1951, J. & A. Churchill, Idid.
49. Laitinen, L.: Craniosynostosis, Ann. paed. Fenn. 2: Suppl. 6, 1956.
50. I,atham, R. A., and Burston, W. It. : 7’11c Postnatal Pattern of (Growth at ille ,Suturcs of
the Human Skull, D. Practitioner 17: 61-67, 1966.
51. Massler, M., and &hour, L: The Growth I’attern of the Cranial X’ault in the Albino Rat
as Measured by Vital Staining With Alizarin Red “S,” Anat. l&z. 110: 83101, 1951,
52. Mednick, L. W., and Washburn, S. L.: Them Role of the Sutures in tho Growth of t,hr:
Braincase of the Infant Pig, Am. J-. Phys. Anthrop. 14: 175191, 1956.
53. Moss, &I. L.: Experiment,al Alteration of Sutural Arca Morphology, Anat. Rec. 1%‘:
569-589, 1957.
54. Moss, M. I,.: Fusion of the Frontal Suture in the Rat, Am. J. Anat. 102: X41-165, 1958.
55. Moss, M. L.: Functional Analysis of liuman Mandibular Growth, J. Pros. Dent. 10:
1149-1159, 1960.
56. Moss, M. L., a,nd Yomung, R. W.: A Functional Approach to Craniology, Am. J. Phys.
Anthrop. 18: 281-292, 1960.
57. Moss, M. L.: Extrinsic Det,ermination of’ Sutural Area Morphology in the Rat Calvaria,
Acta Anat. 44: 263-272, 1961.
58. MOSS, M. L.: The Functional Matrix in Vistas in Orthodontics, edited by B. 8. Kraus
and R. A. Riedel, Philadelphia, 1962, Lea & Febiger, Inc., pp. 85-98.
59. Ortiz, M. II., and Brodie, A. 8: On the Growth of the Human Read From Birth to the
Third Month of Life, Anat. Rec. 103: 311.333, 1949.
60. Petrovic, A. : Personal communication, 1967.
61. Powell, T. V., and Brodie, A. G.: Closure of the Spheno-Occipital Synchondrosis, Anat.
Rec. 147: 15-24, 1963.
62. Pritchard, J. J., Scott, J. H., and Girgis, F. G.: The Structure and Development of
Cranial and Facial Sutures, J. Anat. 90: 73-89, 1956.
63. Ricketts, R. M.: Facial and Denture Changes During Orthodontic Treatment as Analyzed
From the Temporomandibular Joint, AM. J. ORTHODONTICS 41: 163-179, 1955.
64. Robinson, I. B., and Sarnat, B. G.: Growth Pattern of the Pig Mandible. A Serial
Roentgenographic Study Using Metallic Implants, Am. J. Anat. 96: 37-64, 1955.
65. Rosen, M. D., Butcher, E. O., and Silverman, S. I.: Muscle and Skull Developmental
Changes in Dogs With Induced Unilateral Anodontia, Oral Surg., Oral Path. & Oral
Med. 20: 672-675, 1965.
66. Ryijppy, S.: Transplantation of Epiphyseal Cartilage and Cranial Suture, Acta orthop.
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67. Riinning, 0.: The Effect of Papain on the Morphology and Sutural Growth of the Rat
Skull, Suomen Hammaslitik. Toim 60: 112-117, 1964.
68. RSnning, 0.: Observations on the Intracerebral Transplantation of the Mandibular
Condyle, Acta odont. scandinav. 24: 443-457, 1966.
69. Rb;nning, 0.: The Effect of Papain on Transplanted Homologous Synchondroses. To be
published.
70. RGnning, O., Paunio’, K., and Koski, K.: Observations on the Histology, Histochemistry,
and Biochemistry of Growth Cartilages in Young Rats, &omen Hammalii;ik. Toim. 63:
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71. Salzmann, J. A.: Practice of Orthodontics, Philadelphia, 1966, J. B. Lippincott Company,
vol. I.
72. Sarnat, B. G.: Facial and Neurocranial Growth After Removal of the Mandibular Condyle
in the Macaca Rhesus Monkey, Am. J. Surg. 94: 19-30, 1957.
73. Sarnat, B. G.: Postnatal Growth of the Upper Face: Some Experimental Considerations,
Angle Orthodontist 33: 139-161, 1963.
74. Sarnnt, B. G., and Wexler, M. R.: Growth of the Face and Jaws After Resection of the
Septal Cartilage in the Rabbit, Am. J. Anat. 118: 755768, 1966.
75. Scott, J. H.: The Growth of the Human Face, Proc. Roy. Sot. Med. London 47: 91-100,
1954.

Volume 54
Number 8
Cranial growth centers 583
76. Scott, J. 11.: Craniofacial Regions-A Contribution to the Study of Facial Growth, D.
Practitioner 5: 208-214, 1955.
77. Scott, J. H. : Growth at the Facial Sutures, AM. J. ORTHODONTICS 42: 381-387, 1956.
78. Scott, J. H.: The Growth of the Human Skull, J. D. A. South Africa 13: 133-142, 1958.
79. Scott, J. H.: The Cranial Base, Am. J. Phys. Anthrop. 16: 319-348, 1958.
80. Scott, J. H., and Dixon, A. D.: Anatomy for Students of Dentistry, Edinburgh, 1959,
E. & 5. Livingstone, Ltd.
81. Scott, J. H., and Symons, N. B. B.: Introduction to Dental Anatomy, Edinburgh, 1964,
E. & S. Livingstone, Ltd.
82. Sicher, H.: Skeletal Disharmonies and Malocclusions, AM. J. ORTHODONTICS 43: 679-684,
1957.
83. Sicher, H. : Oral Anatomy, St. Louis, 1965, The C. V. Mosby CO.
84. Sijbrandij, S.: Inhibition of Tibia1 Growth by Means of Compression of Its Proximal
Epiphysial Disc in the Rabbit, Acta Anat. 55: 278-285, 1963.
85. Symons, N. B. B.: Studies on the Growth and Form of the Mandible, D. Record 71: 41-53,
1951.
86. Symons, N. B. B.: A Histochemical Study of the Secondary Cartilage of the Mandibular
Condyle in the Rat, Arch. Oral Biol. 10: 579-584, 1965.
87. Tulley, W. J., and Campbell, A. C.: A Manual of Practical Orthodontics, ed. 2, Bristol,
1965, John Wright & Sons, Ltd.
88. Washburn, S. L.: The Effect of Facial Paralysis on the Growth of the Skull of Rat and
Rabbit, Anat. Rec. 94: 163-168, 1946.
89. Watanabe, M., La&in, D. M., and Brodie, A. G.: The Effect of Autotransplantation on
Growth of the Zygomatico-Maxillary Suture, Am. J. Anat. 160: 319-329, 1957.
90. Weinmann, J. P., and Sicher, H.: Bone and Bones, ed. 2, St. Louis, 1955, The C. V.
Mosby Company.
91. Yen, P. K-J., and Shaw, J. H., Studies of the Skull Sutures of the Rhesus Monkey by
Comparison of the Topographic Sampling Technique, Autoradiography and Vital Staining,
Arch. Oral Biol. 8: 349-362, 1963.
92. Yen, P.K.-J., and Shaw, J. H.: Short Versus Long Studies With Radiocalcium at Various
Sites of the Skull of Young and Old Rhesus Monkeys, Arch. Oral Biol. 8: 363-375, 1963.
93. Young, R. W.: The Influence of Cranial Contents on Postnatal Growth of the Skull in
the Rat. Am. J. Anat. 105: 383-415, 1959.
Correction
The May issue of the ANERICAN JOURNAL OF ORTHODONTICS carried a most appropriate
response by Harry Sicher to the presentation of the 1967 Albert H. Ketcham Memorial
Award. In his response, Dr. Sicher paid tribute to the two men who had had a profound
influence in developing his interest in anatomy and orthodontics. The first was Julius
Tandler, described by Dr. Sicher as “one of the ‘greatest teachers [in anatomy1 that I have
ever met.” The other was Albin Oppenheim, whom Dr. Sicher regarded as “years and years
ahead of his time” in orthodontics. The JOURNAL regrets the misspelling of the names of these
two men who were held in such high esteem by Dr. Sicher.