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GOOD MORNING

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D EVELOPMENT OF THE F CE

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THE DEVELOPMENT OF THE FACE OCCURS MAINLY BETWEEN 4 8 WEEKS

Early in the 4 th week, 3 primordialswellings consisting primarily of neuralcrest-derived mesenchyme appeararound the stomodeum and play animportant role in the development offace

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Stomodeum

1 Frontonasal prominence

The single frontonasal prominence ventral to the forebrain

2 Maxillary prominences

The paired maxillary prominences develop from the cranial part of firstpharyngeal arch

3 Mandibular prominences

The paired mandibular prominences develop from the caudal part of first

pharyngeal arch

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THEN FRONTONASAL PROMINENCE GIVES ORIGIN OF 2 PROMINENCE MEDIAL AND LATERAL NASAL

PROMINENCES

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The mandibularprominences fuse and

form the: Chin, lower lip, andlower cheek regions Mandible

The lateral nasal prominences form the alae &side of the nose

The medial nasal prominences fuse and form the intermaxillary segment which gives origin ofcentral part of upper lip, philtrum, upper incissor

with alveolar process and primary palate.

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DEVELOPMENT OF TONGUE

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DEVELOPMENT OF TONGUE

Muscles of the tongue develop formthe occipital somites and innervatedby hypoglossal nerve

Connective tissue of the tonguedevelop form the local mesenchyme

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THE P RIMARY P ALATE

Begins to develop:

Early in the 6 th weekFrom the deep part of

the intermaxillary

segment, as medianpalatine/nasalprocess

Lies behind the premaxillary

part of the maxillaFuseswith the developingsecondary palate

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THE S ECONDARY P ALATE

Begins to develop :Early in the 7 th -8 th weekFrom the internal aspect of themaxillary processes, as lateralpalatine process

2 lateral palatine process fuse atmidline and also with nasalseptum by PALATAL SHELF

ELEVATION

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PALATAL SHELF ELEVATION

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GROWTH OF THE C RANIOFACIAL C OMPLEX

Cranial VaultCranial BaseMaxillaMandible

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GROWTH OF THE C RANIAL VAULT

Prenatal Cranial Vault developed byintramembranous ossicification & postnatal

growth occurs at the sutural margin which isopened by developing brain

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GROWTH OF THE C RANIAL B ASE

The cranial base is composed mostly bybones formed by endochondral ossification.Bands of cartilage are formed between

centers of ossification called synchondrosis:Spheno-occiptal synchondrosisintersphenoid synchondrosis

spheno-ethmoidal synchondrosis

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GROWTH OF THE C RANIAL B ASE

Cranial base grows by endochondralossification that occurs at bothmargins of the synchondrosis.

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P RENATAL DEVELOPMENT OF MAXILLA AND MANDIBLE

Time of developmentRelated processRelated nerve

Related primary cartilageSite of ossification

Related secondary cartilage

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P OST NATAL GROWTH MANDIBLE

post natal growthmandible is occurred

by secondary

cartilaginousgrowth at1. condyle2. coronoid3. symphysis

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P OST NATAL GROWTH MANDIBLE

post natal growthmandible is occurredby

displacement

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P OST NATAL GROWTH MANDIBLE

post natal growthmandible is occurredby surface

remodeling atramus, alveolarprocess, bodyof the mandible

Site of resorption (---) Site of deposition (+++)

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P OST NATAL GROWTH MAXILLA

Post natal growthmaxilla by

displacement

Growth of the surrounding soft tissuestranslates the maxilla downward andforward, opening spaces in the sutures

where bone is added.

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P OST NATAL GROWTH MAXILLA

Post natal growthmaxilla bysutural growth

Midpalatal suture is opened untilteenage years.

Apposition of bone in the molar areaaccounts for space for the third molars.

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P OST NATAL GROWTH MAXILLA

Post natal growthby surface

remodeling asresorption anddeposition ofbone

Site of resorption (---) Site of deposition (+++)

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F ACIAL GROWTH

1. growth in ant.-post. > height> width.2. growth of chin to be prominent3. lower jaw growth is to be more than upper jaw

4. class II malocclusion to be improved5. class III malocclusion to be worse6. teeth come forward more than dental base7. facial planes tend to be horizontal

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THANKS TO ALL