orthodontic insight
Premaxilla: an independent bone that can base
therapeutics for middle third growth!
Mariana Trevizan1, Alberto Consolaro2
DOI: http://dx.doi.org/10.1590/2177-6709.22.2.021-026.oin
Premaxilla, in its early descriptions, had the participation of Goethe. In our face, in a certain period of growth and development processes, premaxilla is an independent and, then, a semi-independent bone to finally be totally integrated to the
maxilla. Formation of the premaxilla acts as a stabilization element inside the facial skeleton comparable to the cornerstone
of a Roman arch and is closely related to the development of human face and its abnormal growth with characteristic malformations. Until when the premaxillary-maxillary suture remains open and offers opportunities to orthopedically influence facial growth to exert influence over facial esthetics and function? Contact with preliminary results in 1183 skulls from
anatomic museums at USP, Unicamp and Unifesp led us to question therapeutic perspectives and its clinical applicability.
Keywords: Premaxilla. Facial growth. Incisive suture. Goethe.
A descrição inicial da pré-maxila teve a participação de Goethe. Na face, em determinado período do crescimento e desenvolvimento, têm-se a pré-maxila como um osso independente e, depois, semi-independente para, finalmente, se integrar
totalmente à maxila. A formação da pré-maxila atua como um elemento estabilizador dentro do esqueleto facial, comparável
com a pedra angular de um arco romano, e está intimamente relacionada com o desenvolvimento da face humana e seu
crescimento anormal, com malformações características. Até quando a sutura pré-maxilar-maxilar continua aberta e oferece
oportunidades para se influenciar ortopedicamente o crescimento facial e modificar a estética e função da face? O contato
com estudos preliminares em 1.183 crânios de museus anatômicos da USP, Unicamp e Unifesp nos induziu a questionar
sobre as perspectivas terapêuticas e aplicabilidades clínicas.
Palavras-chave: Pré-maxila. Crescimento facial. Sutura incisiva.
How to cite this article: Trevizan M, Consolaro A. Premaxilla: an independent
bone that can base therapeutics for middle third growth! Dental Press J Orthod.
2017 Mar-Apr;22(2):21-6.
DOI: http://dx.doi.org/10.1590/2177-6709.22.2.021-026.oin
1
Post-graduation program in Pediatric Dentistry, Dental School of Ribeirão Preto,
Universidade de São Paulo (FORP-USP).
2
Full professor, Dental School of Bauru, Universidade de São Paulo (FOB-USP) and
Post-graduation program at the Dental School of Ribeirão Preto, Universidade de São
Paulo (FORP-USP).
Submitted: February 06, 2017 - Revised and accepted: February 13, 2017
» The authors report no commercial, proprietary or financial interest in the products
or companies described in this article.
Contact address: Alberto Consolaro
E-mail: consolaro@uol.com.br
© 2017 Dental Press Journal of Orthodontics
21
Dental Press J Orthod. 2017 Mar-Apr;22(2):21-6
orthodontic insight
Premaxilla: an independent bone that can base therapeutics for middle third growth!
The face is divided into upper third, middle third
(midface) and lower third. Maxilla is the main bone
of midface and shows prevailing vertical growth associated to the skull base. In the first years of postnatal
life, skull growth predominates over facial growth.6,7
At the same time, mandibular growth is exuberant
and maxillary growth is reduced.
In the first ten years of life, there is predominantly horizontal maxillary growth towards the anterior and posterior region8. In the second decade
of life, vertical growth prevails. The present study
represents a second phase of author’s reflections on
the premaxilla; and conclusions are similar to those
previously published.38 Some other information was
added to the present study, besides the arguments
presented at that time, thus enhancing the first study
aforementioned.
When explaining facial growth and development in childhood, Enlow and Dale14 described that
there is a displacement of the nasomaxillary complex
as a result of the increase in soft tissues in the face.
The bones of the nasomaxillary complex get dislocated to positions far from their several suture joints.
A new bone is simultaneously added to the suture
margins of each bone, broadening the perimeter of
each bone by means of quantities that amount to extensions of the regional dislocation.
Premaxilla is also known as incisive bone, intermaxillary bone and premaxillary bone, or even
Goethe’s bone. Its discovery in humans can be romantically attributed to Goethe18 (1784) for he was,
perhaps, the greatest genius of German culture, even
though there are reports that precede his mention.9
The first illustration of the incisive suture in humans was presented in 1573 by Coiter.11 In 1779,
Broussonet (cited by Brauning-Oktavio,9 1956)
and, right after that, in 1780, Vicq d’Azyr (cited by
Brauning-Oktavio9, 1956), pioneered to describe
it as anatomists reporting it as a medial part of the
maxilla that represented a bone separate from the
skull in vertebrates.
Premaxilla growth is closely related to the development of human face,3 yet, with respect to premaxillary growth and development, it has not been
defined yet the period in which the premaxilla/maxilla suture closure occurs, so that they can constitute
a single bone.
© 2017 Dental Press Journal of Orthodontics
Abnormal growth of the premaxilla in relation to
the maxilla may be correlated to malformation, such
as prognathism, deep bite and protrusion.3 Formation of the premaxilla acts as a stabilization element
inside the facial skeleton, comparable to the cornerstone of a Roman arch. In other words, premaxilla
is closely related to the development of human face
and its abnormal growth may be related to characteristic malformations.
Thoroughly and sequentially understanding the
development of the premaxilla and its integration to
the maxilla can:
1) Base and stimulate the formulation of new
ways for the treatment of growth and development alterations in the maxilla and the midface
with the use of anteroposterior expansion of the
maxilla.
Orthodontic appliances could conduct the premaxilla to a more beneficial anterior position20,32,34 by
the premaxillary-maxillary suture opening, stimulating the development of that region34 and be a contribution factor in non-surgical maxillary protraction
through stimulation of maxillary sutures.20
For instance, the suture that exists between premaxilla and maxilla can be the adequate point for
intervention in Class III cases in which the diagnosis indicates lack of maxillary development. Considering the existence of premaxilla as an independent
bone would enable its movement via suture and/or
periosteal bone growth, in order to correct certain
malocclusions, reducing risk and seriousness, or even
avoiding some surgical procedures.
2) Help with understanding the etiopathogeny of cleft lip and cleft palate and their outcomes
in craniofacial growth, allowing the planning of
more refined and pertinent treatments of such
development disorders.
The position of the clefts is not always identical to
the premaxillary-maxillary suture3,21, since bone development does not match to primary facial development.21 Face formation lines are not identical to the
gathering of bone growth centers in all the sutures,
including those of the premaxillary-maxillary suture.
Bilateral cleft lip and cleft palate cause premaxillary protrusion, including infra-nasal and teeth soft
tissues.4 Its treatment goes through several stages,
among them alveolar bone grafting,23 which can be
22
Dental Press J Orthod. 2017 Mar-Apr;22(2):21-6
Trevizan M, Consolaro A
orthodontic insight
autogenous or synthetically produced grafts,19 extinguishing failure.
The existence of premaxilla as an independent
bone would enable its movement after relocation,
which occurs precociously, in a way that the defect
is reduced before grafting execution, leading it to a
more favorable position.
3) Base and stimulate current and new therapeutics for nasal obstruction cases in newborn
children for congenital nasal pyriform aperture
stenosis.
Nasal obstruction is a potentially serious condition to infants,15 once it may lead to respiratory
failure of newborn children.10 Among the etiologies,
there is congenital nasal pyriform aperture stenosis,
which narrows the anterior third of the nasal cavity,
caused by excessive growth of maxillary medial nasal
process.29
The intermaxillary bone, or premaxilla, constitutes the main limit of the pyriform apertures, and
parts of such bone can be occasionally seen on the laterals to the pyriform apertures up to five years of life
approximately, together with the nasal bone, which
closes the pyriform aperture and is in contact with
the frontal bone.3
» the palatine process,
» and the Stenonianus process, which goes along
with the cartilage of the nasal septum and the
vomer.3,27
Embryonically, the face derives from prominences
that surround a central depression called stomodeum,
which will turn out to be the oral cavity. At the embryonic stage, there are six pharyngeal arches, and the
first one origins from the maxilla and the mandible.
Later, leveling of the medial nasal and frontonasal
processes will originate the nose, maxilla and primary
palate. The lateral nasal process also participates in
the formation of the maxilla and the nose.
The premaxilla starts ossification in the 7th month
of pregnancy.28 In such period, there is a change in
blood supplementation of the face that occurs concurrently with a critical period of intermediate development of the face and the palate.
As incredible as it may seem, existence of the premaxilla as an independent or semi-independent bone
has already been questioned,5,26,35,36 for it is difficult to
embryonically identify its ossification center.
Clarifying up to when the premaxilla, in terms of
time, can be considered independent or semi-independent — since even adults have it partially or totally persistent20 — can create new opportunities in
orthopedics, orthodontics and surgeries involving
the region to correct disorders in craniomandibular
growth and development.
In order to topographically determine and identify
the approximate closure time of the suture between
the maxilla and the premaxilla, exploring their morphology, function and relevance in the human skeleton, Trevizan37 has been doing research with over
1183 skulls at varying gestational and postnatal ages
from the anatomic museums of USP, Unicamp and
Unifesp universities. Preliminary results show that
the premaxilla must be considered independent on
the maxilla up to a certain precocious stage of postnatal life, but it can be extended throughout life, being
semi-independent on the maxilla.
The premaxillary-maxillary suture, also known as
incisive suture, can be identified in the palate of the
skulls even in adults, but it has been reported that its
closure occurs in the third semester of prenatal life.1,2,22,24
Its closure on the buccal surface of the alveolar process
may happen very precociously, but what about the
WHAT IS THE IMPORTANCE OF THE
PREMAXILLA AND ITS PROSPECTIVE CLINICAL
IMPLICATIONS?
The prefix ‘pre’ implies anteriority, antecedence
or precedence. The nominal definition of the premaxillary bone indicates the one that precedes or is
ahead of the maxilla and skull.
The premaxilla is the intermaxillary segment of
the maxilla where the four upper incisives are placed.3
It develops embryonically from the primary palate.25,28
The limits of the premaxilla are signaled by a
lateral structure that starts in the incisive foramen
towards the region between lateral incisives and canines, forming what was once called incisive bone.28
The route of the suture descends from the junction
of maxilla and premaxilla, near the pyriform aperture
in its lower portion, until the alveolar margin in the
region of the canine, transposing the palate until the
incisive foramen22 (Figs 1 and 2).
We can distinguish three parts in the premaxilla:
» the alveolar part with facial process,
© 2017 Dental Press Journal of Orthodontics
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orthodontic insight
Premaxilla: an independent bone that can base therapeutics for middle third growth!
A
B
Figure 1 - Premaxillary-maxillary suture in a child’s skull.
A
B
Figure 2 - Premaxillary-maxillary suture in an adult’s skull.
other areas? What would be the course or sequence of
the closure of such suture in all its anatomic interfaces?
In parallel, questioning and controversy remain:
“Up to where these results on the premaxilla and the premaxillary-maxillary suture will be able to withstand treatment
protocols of craniomandibular growth disorders as it happens
with the midpalatal suture, especially regarding procedures for
maxillary expansion/position and volume increase?”
© 2017 Dental Press Journal of Orthodontics
The particularities of the premaxillary-maxillary
suture are probably associated to the way and mechanisms of maxillary growth whose remodeling happens from upper to lower13, offering a more precocious closure than the midpalatal suture, which must
be a concentration point of forces related to craniomandibular growth, since it is directly linked to the
skull base! Yet, in adults, this suture can be observed5.
24
Dental Press J Orthod. 2017 Mar-Apr;22(2):21-6
Trevizan M, Consolaro A
orthodontic insight
HISTORICAL ASPECTS AND EVOLUTION
OF KNOWLEDGE ON THE PREMAXILLA IN
HUMANS
Discussion on the existence of a separate intermaxillary bone in humans seems to be as old as the
history of comparative anatomy. Since then, the premaxilla or intermaxillary bone has a central place in
the discussion on dissimilarity or homology between
men and other vertebrates.
In Camper’s concept in 1778 (cited by BrauningOktavio,9 1956), the division of maxilla “between the
incisive and the canine teeth” is considered one of
the main differences between humans and monkeys.
According to Goethe, accident and reflection guided
him in his research with various skulls of animals and
humans. It is not only the anatomic discovery that
made Goethe’s work so famous and important, but
the idea according to which there was natural harmony among vertebrates, including men, for which a
especial position was intended.17
Goethe started his morphological studies in
1781 as a student of his friend Loder, professor of
Anatomy in Jena (cited by Franz,16 1933).His first
booklets on the intermaxillary bone were published
in 1784/1786 and a new edition was republished in
1981. In Goethe’s letters, we see: “I have found neither gold, nor silver, but what makes me one of us,
that is, the presence of the intermaxillary bone in
humans!” (cited by Voss,33 1979).
Nevertheless, it was also Vicq d’Azyr (cited by
Brauning-Oktavio,9 1956) who discovered the intermaxillary bone, which he called anterior maxilla, in
unborn children, and presented it in his “Memories”
© 2017 Dental Press Journal of Orthodontics
at the Science Academy, in Paris, 1780. According to
Barteczko and Jacob3 (2004), the merits of such discovery are owed to Vicq d’zur, even though both Goethe
and Vicq d’Azyr described it independently and with
different methods. Perhaps, Volcher Coiter11,12 (1573
and 1573/1955) was the first one to do that, when,
in an illustration of the incisive suture, he wrote only
“upper maxillary bone in an adult, with number and
position of the interviewee”. Although Goethe was
not the first one to discover the premaxillary, his involvement brought great philosophical and ideological
importance to the subject. It may be scary, but we still
find authors who deny a separate premaxilla.30,31,36
FINAL CONSIDERATIONS
1. We are still in search of several explanations for
the results of the analysis of 1183 human skulls from
anatomic museums of USP, Unicamp and Unifesp
universities, to be presented soon.
2. How can we use them in therapeutic diagnoses
and planning of the patients with altered development
of the midface if we still do not even know how and
when the premaxillary-maxillary suture disappears?
3. Stimulating critical thinking by presenting preliminary questions and results represents a way of collecting subsides and increase the amplitude of their
explanations in clinical practicing.
The premaxilla having a period as an independent
bone seems unequivocal as well as the fact that we
will be able to use it in therapeutics. We are now exploring the perspectives on using the premaxillarymaxillary suture in order to influence the growth of
the middle third of the face!
25
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orthodontic insight
Premaxilla: an independent bone that can base therapeutics for middle third growth!
REFERENCES
1.
Ashley-Montagu MF. The premaxilla in primates. Q Rev Biol.
21.
1935;10(1):32-59.
2.
Ashley-Montagu MF. The premaxilla in primates. Q Rev Biol.
22. Noback CR, Moss ML. The topology of the human premaxillary bone.
1935;10(2):181-208.
3.
Am J Phys Anthropol. 1953 June;11(2):181-8.
Barteczko K, Jacob M. A re-evaluation of the premaxillary bone in
23. Precious DS. A new reliable method for alveolar bone grafting at about 6
humans. Anat Embryol (Berl). 2004 Mar;207(6):417-37
4.
years of age. J Oral Maxillofac Surg. 2009 Oct;67(10):2045-53.
Baxter DJ, Shroff MM. Developmental maxillofacial anomalies. Semin
24. Remmelink IlL The postnatal development of the human maxillary
Ultrasound CT MR. 2011 Dec;32(6):555-68.
5.
sutural surfaces [thesis]. Groningen, The Netherlands: The University of
Behrents RG, Harris EF. The premaxillary-maxillary suture and orthodontic
Groningen; 1985.
mechanotherapy. Am J Orthod Dentofacial Orthop. 1991 Jan;99(1):1-6.
6.
Bishara SE. Orthodontia. São Paulo: Ed. Santos; 2004.
7.
Bishara SE. Textbook of Orthodontics. St. Louis: WB Saunders; 2000.
8.
Björk A, Skieller V. [Growth and development of the maxillary complex].
25. Revelo B, Fishman LS. Maturational evaluation of ossification of
the midpalatal suture. Am J Orthod Dentofacial Orthop. 1994
Mar;105(3):288-92.
26. Rygh P, Tindlund R. Orthopedic expansion and protraction of the maxilla
Inf Orthod Kieferorthop. 1984;16(1):9-52.
9.
in cleft palate patients--a new treatment rationale. Cleft Palate J. 1982
Bräuning-Oktavio H. Vom Zwischenkieferknochen zur Idee des Typus.
Apr;19(2):104-12.
Goethe als Naturforscher in den Jahren 1780–1786. Barth: Leipzig; 1956.
27.
Nouv Acta Leopoldina n. 126, Bd.18.
1955 Jan;121(1):13-28.
stenosis. Laryngoscope 1989;99:86-91.
28. Sperber GH, Sperber SS, Guttmann GD. Craniofacial embryogenetics and
Coiter V. Externarum et internarum principalium humani corporis partium
development. 2nd ed. Shelton: People’s Medical; 2010.
tabulae, atque anatomicae exercitationes observationesque variae.
29. Tagliarini JV, Nakajima V, Castilho EC. Congenital nasal pyriform aperture
Noribergae: Gerlatz; 1573.
12.
stenosis. Braz J Otorhinolaryngol. 2005 Mar-Apr;71(2):246-9.
Coiter V. Externarum et internarum principalium humani corporis partium
30. Vacher C, Onolfo JP, Lézy JP, Copin H. [The growth of the maxilla in
tabulae atque anatomicae. Opuscula selecta Neerlandicorum de arte
humans. What place for the premaxilla?]. Rev Stomatol Chir Maxillofac.
medica. Bohn: Harlem; 1573-1955.
13.
2001 June;102(3-4):153-8.
Delaire J. [Lateral limits of the os incisivum. (Studies of some congenital
31.
malformations)]. Fortschr Kieferorthop. 1965;26(4):391-5. German.
14.
Enlow DH, Dale JG. Crescimento e desenvolvimento facial na infância.
July;38(4):330-6.
32. Vardimon AD, Graber TM, Voss LR, Verrusio E. Magnetic versus
Koogan; 2001. p. 393-432.
mechanical expansion with different force thresholds and points of force
Faust RA, Phillips CD. Assessment of congenital bony nasal obstruction
application. Am J Orthod Dentofacial Orthop. 1987 Dec;92(6):455-66.
by 3-dimensional CT volume rendering. Int J Pediatr Otorhinolaryngol.
33. Voss H. Goethes Selbstzeugnisse über seine Beschäftigung mit
2001 Oct 19;61(1):71-5.
16.
“organischen Naturen”. II. Briefe (1776 bis 1817). Gegen-Baurs Morphol Jb.
Franz V. Goethes Zwischenkieferpublikation nach Anlaß, Inhalt und
1979;125:466-518.
Wirkung. Z Anat Entw.-Gesch. 1933;30:469-543.
17.
34. Witzig JW, Spahl TJ. The clinical management of basic maxillofacial
Goerttler K. Hrsg Entwicklungsgeschichte des Menschen. Berlin:
orthopedic appliances. Mechanics. Littleton: PSG; 1987. p. 226-8, 236-7, 240.
Springer; Göttingen Heidelberg; 1950.
18.
35. Wood NK. Osteogenesis of the human upper jaw: proof of the non-
Goethe VW. Über den Zwischenkiefer des Menschen und der
existence of a separate premaxillary centre. Arch Oral Biol. 1969
Tiere. Handschriftlich: mit Tafeln, März; 1784; ohne Tafeln 1820 zur
Nov;14(11):1331-9.
Morphologie, Band I Heft 2: “Dem Menschen wie den Tieren ist ein
36. Wood NK, Wragg LE, Stuteville OH. The premaxilla: embryological
Zwischenknochen der obern Kinnlade zuzuschreiben”; 1831 mit Tafeln
evidence that it does not exist in man. Anat Rec. 1967 Aug;158(4):485-9.
in den “Verhandlungen der Kaiserlich Leopoldinisch-Carolinischen
37.
Akademie der Natur- forscher”.
19.
Vacher C, Sakka M, Dauge MC. Incisive suture (fissure) in the human
fetus: radiographic and histologic study. Cleft Palate Craniofac J. 2001
In: Ten Cate R. Histologia Bucal. 5a ed. Rio de Janeiro: Guanabara
15.
Shepherd WM, McCarthy MD. Observations on the appearance and
ossification of the premaxilla and maxilla in the human embryo. Anat Rec.
10. Brown OE, Myer CM, Manning SC. Congenital nasal pyriform aperture
11.
Lisson JA, Kjaer I. Location of alveolar clefts relative to the incisive fissure.
Cleft Palate Craniofac J. 1997 July;34(4):292-6.
Trevizan M. Sutura pré-maxilar-maxilar: aspectos topográficos e
temporais de sua presença [mestrado]. Ribeirão Preto (SP): Universidade
Hallman M, Thor A. Bone substitutes and growth factors as na alternative/
de São Paulo; 2017. No prelo.
complement to autogenous bone for grafting in implant dentistry.
38. Trevisan M, Consolaro A. A pré-maxila é um osso independente até
Periodontol 2000. 2008;47:172-92.
quando? A sutura pré-maxilar-maxilar pode fundamentar terapêuticas
20. Haskell BS, Farman AG. Exploitation of the residual premaxillary-maxillary
para o crescimento do terço médio da face! Rev Clín Ortod Dental Press.
suture site in maxillary protraction. An hypothesis. Angle Orthod. 1985
2017 Fev-Mar;16(1):122-6.
Apr;55(2):108-19.
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