POSTNATAL GROWTH OF MAXILLA ANOMALIES CLINICAL IMPLICATIONS CLINICAL SIGNIFICANCE REFERENCES

2. POSTNATAL GROWTH OF
MAXILLA
PRESENTATION BY:
DR. DEVENDER KUMAR
1ST YEAR PG
DEPT. OF ORTHODONTICS

3. CONTENTS
• INTRODUCTION
• POSTNATAL GROWTH OF MAXILLA
• ANOMALIES
• CLINICAL IMPLICATIONS
• CLINICAL SIGNIFICANCE
• REFERENCES

4. INTRODUCTION
The maxilla is the second largest bone of the
facial skeleton, the first being the mandible. It
is a pneumatic bone that is paired and forms
the upper jaw.
It is an irregularly shaped bone that contributes
to the formation of the roof of the oral cavity,
the orbit, the nasal cavity, the infratemporal
fossa and the pterygomaxillary fossa.

5. The body of the maxilla has four surfaces:
• Anterior or facial surface
• Posterior or infratemporal surface
• Superior or orbital surface
• Medial or nasal surface.
It has four processes:
• Frontal
• Zygomatic
• Alveolar
• Palatine.

6. Growth and Development of
Maxilla
Will be considered in 2 periods:
1. Prenatal period (intra uterine).
a. Pre-embryonic (0-14 days).
b. Embryonic (14-55 days).
c. Foetal (56-270 days).
2. Post natal period (extra uterine).

7. Postnatal Growth of Maxilla
• The growth of nasomaxillary complex is
produced by following mechanism:
1. Displacement
2. Growth at sutures
3. Surface remodelling

9. Displacement
• Displacement – here the whole bone is carried by a
mechanical force
• Site -Articular contacts
• 1 displacement –the physical carry takes place in
conjunction with the bones own enlargement
• vectors oriented–posteriorly
and superiorly
• bone displaced –
anteriorly and inferiorly

10. • 2 displacement - movement of bone and soft
tissues not directly related to its enlargement.
• Temporal lobe of cerebrum
• Middle cranial fossa
• Displace nasomaxillary complex downwards
and forwards

12. Growth at Sutures
• The maxilla is connected to the cranium
and cranial base by a number of sutures.
• These includes
1. Fronto-nasal suture
2. Fronto-maxillary suture
3. Zygomatico-temporal suture
4. Zygomatico-maxillary suture
5. Pterygo-palatine suture

14. Surface Remodelling
• Remodeling is a process of reshaping
and resizing a growing bone as it is
relocated to new levels.
• Reason- while parts of bone are moved;
it maintains the form of the whole bone
and causes its enlargement.

15. • carried out by the osteogenic membranes and
other surrounding soft tissues
• bone itself contributes by feedback
information
–Bionator-tries to alter this equilibrium
• Fields of remodeling- resorptive and
depository on the outside and inside of bone
• Clinical significance-distalisation of molar

16. • Massive bone remodelling by
deposition and resorption occurs and
bring about :
1. Increase in size
2. Change in shape of bone
3. Change in functional relationship

17. Maxillary Tuberosity and Arch
Lengthening
• Remodeling at the maxillary tuberosity causes
horizontal lengthening. It is a depository field,
hence causes lengthening and widening of the
arch and provides space for the eruption of
molars.
• Allows the clinician to “expand the arch” by
distalization of molars into an area of bone
deposition.

19. Lacrimal Suture
• The lacrimal bone is a bony island with its
entire perimeter bounded by sutural
connective tissue contacts separating it
from many other surrounding bones.

20. Key Ridge
• Major change in surface contour occurs
along the vertical crest just below the
malar protuberance called the key ridge.

21. Alveolar Ridges
• It occurs by bone deposition at alveolar
margins.
• It is termed as vertical drift.
• This increases the maxillary height and depth
of palate

22. Palatal Remodelling
• The external labial side of the whole
anterior part of the maxillary arch is
resorptive with bone being added into the
inside of the arch, the arch increases in
width and the palate becomes wider.
• (V Principle)

23. Nasal cavity
• The lining surface of the bony walls and floor
of the nasal chambers are predominantly
resorptive, which produces a lateral and
anterior expansion of the nasal chambers.

24. Zygomatic Bone
Apposition occurs on the
posterior surface of the
zygomatic process, with
simultaneous resorption on
its anterior or facial surface.
This region moves in a
posterior direction towards
the base of the skull as the
entire maxillary bone
increases in size.

25. Maxillary Sinus
• The lining cortical surface of the sinus
are all resorptive except the medial nasal
wall which is depository as it remodels
laterally to accommodate nasal expansion.

26. Downward Maxillary Displacement
• The primary displacement of the
whole ethmomaxillary complex in an
inferior direction is accomplished by
simultaneous remodelling in all areas,
inside and out throughout the entire
nasomaxillary region.

27. Maxillary Height
• Classic implant studies of Bjork and
Skiellerlo confirm that maxillary height
increases because of sutural growth
towards the frontal and zygomatic bones
and appostional growth in the alveolar
process.

28. Maxillary Width
• Growth in the median suture is more important
for appositional remodeling in the development
of maxillary width.
• Growth increases at the median suture mimic
the general growth curve for body height.
• Maximum pubertal growth in the median suture
coincides with the time for maximum growth in
the facial sutures as seen in the profile
radiograph.

29. Maxillary Length
• Length increases in the maxilla after about the
second year, occurs by apposition on the
maxillary tuberosity and by sutural growth
toward the palatine bone.
• Bjork and Skieller’s implant studies show that
anterior surface to be rather stable sagitally, but
the maxillary arch is remodeling as it grows
downward, which is why the anterior region is
resorptive.

30. Anomalies and Clinical
Implications
1. Cleft lip & Palate :

31. 2) Microstomia and
Macrostomia :
Merging of the maxillary and
mandibular prominences beyond or
short of the site for normal mouth
size results in a mouth that is too
small (microstomia) or too wide
(macrostomia)

32. Microstomia

33. Macrostomia

34. 3) Oblique facial cleft :
An oblique facial cleft results from
persistence of the groove between the
maxillary prominences and the lateral nasal
prominences running from the medial canthus
of the eye to the ala of the nose.

36. 4) Craniofacial development cyst :
Developmental cysts arise along the
lines of facial cleft and their lining
epithelia appear to be derived from residues
or “rests” of the covering epithelia of the
embryonic prominences that merges to
form the face.

37. Clinical Significance :
1. Maxilla is formed form the first branchial arch
and ectomesenchymal cells. Any etiological
factors which interfere with the function of this
structure may give rise to under developed
maxilla.
2. Maxilla forms the middle 1/3rd of the face,
hence underdevelopment leads to midface
deficiency especially in cases of trauma to the
nose.

38. 3. Mid palatine suture closes around 15-19
years uptill which age the transverse
growth continues and can be utilized for
expansion of narrow arch by RME or
SME.
4. Maxilla is surrounded by an envelope of
facial muscles restricted growth of which
can retard the growth of maxilla.
Eg: Scarring after CLP repair

39. 5. Vertical lengthening of maxilla is equal in both
anterior and posterior regions and any
discrepancies can cause open bite or deep bite.
6. Development of dentition is directly related to
development of alveolar bone which in turn is
related to vertical height.
7. Maxilla to cranial base = 82° Steiners analysis.
Less than 82 – Retrognathic maxilla
More than 82 – Prognathic maxilla.
8. Growth spurts
9. Orthognathic sugery

40. References :
• Sperber’s craniofacial development
• Essential of facial Growth : Enlow
• Inderbir Singh : Human Embryology
• B.D. Chaurasia Human Anatomy, Vol. 3
• Contemporary Orthodontics – William R.
Proffit.
• Baily and Love’s - Short practice of
surgery, 23rd Edition.

41. Thank You