Developmental disturbances of the jaws- Maxilla, Mandible

2. Agnathia
Micrognathia
Macrognathia
Facial hemihypertrophy
Facial hemiatrophy

3. Agnathia
It’s a rare condition characterized by absence of
max or mand
due to failure in development of the jaw.

4. MICROGNATHIA
 small jaw
 may affect the max or mand
 Bird face appearance

5.  Micrognathia of the maxilla presents
 deficiency in the premaxillary area,
 middle third of face appears retracted;
 mouth breathing owing to associated maldevelopment
of nasal and nasopharyngeal structures.
 Severe retrusion of chin, steep mandibular angle, deficient
chin button

6.  True micrognathia could be congenital or
acquired
 sometimes it may be associated with other
abnormalities or may be a part of syndrome
 Pierre Robin syndrome
 Congenital heart disease
 The acquired type usually result from defect in TMJ such
as trauma & infection.

7. Pierre Robin syndrome
(Robin sequence, Pierre Robin Anomalad, Robin
complexes, Pierre Robin Malformation)
 French dentist- Pierre Robin
 Classic triad- present at birth in which an infant
has
 very small lower jaw,
 tongue that tends to fall back and downward
 cleft palate

8. Bird facies appearance

9. complications
 Tongue falls back obstruct airway
 Choking
 Infections
 Feeding difficulties
 Nasal deformities

10. Mandibulofacial Dysostosis
Bird like or fish like facies

11.  First pharyngeal arch- mandibular arch
 develops during 4th week of development
 Develops into maxillary and mandibular process
 Maxillary process- maxilla & palate
 Mandibular process- mandible

12. Chromosome defect- 5q32- q33.1

14. Macrognathia
 abnormally large jaw
 increase of both jaw size
 This condition could be secondary to other
diseases, as in Paget’s disease (overgrowth of
cranium & max/mandible) & in Acromegally
(mand).

15. Facial hemihypertrophy/
hemihyperplasia
 Hyperplasia of tissues
 Significant unilateral enlargement of the face
(frontal bone, maxilla, palate, mandible, alveolar
process, condyle and associated soft tissues);
usually the right side

16.  Classification:
 Complex hemihyperplasia: involvement of half of the
body (atleast one arm & one leg)
 Single hemihyperplasia: involvement of a single limb
 Hemifacial hyperplasia: one side of the face
 Etiology: unknown
 vascular or lymphatic abnormalities, CNS disturbances,
chromosomal abnormalities

17. Malformation syndromes associated with hemihyperplasia:
 Beckwith- Wiedemann syndrome
 Neurofibromatosis
 Albright syndrome
 Multiple exostoses syndrome
 Segmental odontomaxillary dysplasia

18.  C/F:
 Females more affected
 Unilateral macroglossia with contralateral
displacement
 roots and crowns of the teeth are often enlarged
and may prematurely erupt

19. Oral manifestations
 dentition of the hypertrophic side is abnormal in three
aspects:
 tooth size, shape & rate of development
 Tongue-
 enlarged lingual papillae, unilateral enlargement with
contralateral displacement
 Buccal mucosa- thick, velvety folds

20. Facial hemiatrophy
 Parry Romberg-syndrome/
 Hemifacial atrophy
 A characteristic loss in the soft tissues of
essentially half the face.
 progressive wasting of subcutaneous fat,
sometimes accompanied by atrophy of skin and
sometimes bone and muscle.
 1st or 2nd decade of life
 affected side hyperpigmented

21.  It may occasionally spread to the neck and one side of
the body and
 is usually accompanied by
 contralateral Jacksonian epilepsy,
 trigeminal neuralgia,
 nevi,
 ocular complications

22. ‘Coup de sabre’ –
 painless cleft near the midline of face or forehead.
 Marks the boundary between normal & atrophic
tissues
 Bluish hue may appear in the skin overlying atrophic
fat.

23.  hollowing of cheek and the orbit
 jaw bones and roots of teeth on affected side may
exhibit delayed development and retarded tooth
eruption
Etiology:
peripheral nerve dysfunction, trauma, infection,
heredity

24. Thank You