Growth and development of cranium and maxilla..

GROWTH AND DEVELOPMENTGROWTH AND DEVELOPMENT
OF CRANIUMOF CRANIUM
ANDAND
MAXILLAMAXILLA
www.indiandentalacademy.comwww.indiandentalacademy.com

CONTENTSCONTENTS
 INTRODUCTIONINTRODUCTION
 CRANIUMCRANIUM
 CALVARIACALVARIA
 GROSS ANATOMYGROSS ANATOMY
 PRENATAL GROWTHPRENATAL GROWTH
 OSTEOGENESISOSTEOGENESIS
 FONTANELLESFONTANELLES
 CRANIAL BASECRANIAL BASE
 ANATOMYANATOMY
 PRENATAL GROWTHPRENATAL GROWTH
 CHONDRIFICATION CENTRESCHONDRIFICATION CENTRES

 SUTURESSUTURES
 SYNCHONDROSISSYNCHONDROSIS
 CRANIAL BASE ANGULATIONCRANIAL BASE ANGULATION
 ANOMALESANOMALES
 MAXILLAMAXILLA
 EMBRYOLOGYEMBRYOLOGY
 PALATEPALATE
 POSTNATAL REMODELLINGPOSTNATAL REMODELLING
 THEORIES OF GROWTHTHEORIES OF GROWTH
 ANOMALIESANOMALIES

THE MOBILE MASK IN FRONT OFTHE MOBILE MASK IN FRONT OF
HUMAN BRAIN BEGAN TO ATTRACTHUMAN BRAIN BEGAN TO ATTRACT
OUR ATTENTION WHEN WE WEREOUR ATTENTION WHEN WE WERE
BABIES AND CONTINUES TOBABIES AND CONTINUES TO
FASCINATE US AS LONG AS WE LIVE.FASCINATE US AS LONG AS WE LIVE.
,,
W. K. GREGORYW. K. GREGORY

INTRODUCTIONINTRODUCTION
DEFINITIONSDEFINITIONS
 GROWTHGROWTH
ROBERT E MOYERS HAS DEFINED GROWTHROBERT E MOYERS HAS DEFINED GROWTH
AS NORMAL CHANGES OCCURING IN AMOUNT OFAS NORMAL CHANGES OCCURING IN AMOUNT OF
SUBSTANCES. ACCORDING TO HIM, GROWTH ISSUBSTANCES. ACCORDING TO HIM, GROWTH IS
QUANTITATIVE ASPECT OF BIOLOGIC DEVELOPMENTQUANTITATIVE ASPECT OF BIOLOGIC DEVELOPMENT
MEASURED PER UNIT TIME.MEASURED PER UNIT TIME.
 DEVELOPMENTDEVELOPMENT
IT REFERS TO ALL THE NATURALLYIT REFERS TO ALL THE NATURALLY
OCCURING UNIDIRECTIONAL CHANGES IN THE LIFEOCCURING UNIDIRECTIONAL CHANGES IN THE LIFE
OF AN INDIVIDUAL FROM ITS EXISTENCE AS AOF AN INDIVIDUAL FROM ITS EXISTENCE AS A
SINGLE CELL TO ITS ELABORATION AS ASINGLE CELL TO ITS ELABORATION AS A
MULTIFUNCTIONAL UNIT TERMINATING TO DEATH.MULTIFUNCTIONAL UNIT TERMINATING TO DEATH.www.indiandentalacademy.comwww.indiandentalacademy.com

CRANIUMCRANIUM
 THE DEVELOPMENT 0F SKULL, COMPRISINGTHE DEVELOPMENT 0F SKULL, COMPRISING
BOTH THE CRANIUM AND MANDIBLE, IS ABOTH THE CRANIUM AND MANDIBLE, IS A
BLEND OF 3 MAIN SKULL ENTITIES-BLEND OF 3 MAIN SKULL ENTITIES-
1) NEUROCRANIUM1) NEUROCRANIUM
- SKULL VAULT OR CALVARIA OR- SKULL VAULT OR CALVARIA OR
DESMOCRAIUMDESMOCRAIUM
- CRANIAL BASE OR CHONDROCRNIUM.- CRANIAL BASE OR CHONDROCRNIUM.
2) FACE OR OROGNATHOFACIAL COMPLEX2) FACE OR OROGNATHOFACIAL COMPLEX
. SPLANCHNOCRANIUM. SPLANCHNOCRANIUM
OR VISCEROCRANIUMOR VISCEROCRANIUM
3) MASTICATORY APPARATUS.3) MASTICATORY APPARATUS.www.indiandentalacademy.comwww.indiandentalacademy.com

 THREE SKULL ENTITIES ARISE FROMTHREE SKULL ENTITIES ARISE FROM
I)NUERAL CREST CELLSI)NUERAL CREST CELLS
II)PARAXIAL MESODERM TISSUEII)PARAXIAL MESODERM TISSUE

CALVARIACALVARIA

GROSS ANATOMYGROSS ANATOMY

NORMA VERTICALISNORMA VERTICALIS

NORMA OCCIPITALISNORMA OCCIPITALIS

NORMA LATERALISNORMA LATERALIS

NORMA FRONTALISNORMA FRONTALIS

3 MAJOR TYPES OF GROWTH AT3 MAJOR TYPES OF GROWTH AT
CELLULAR LEVELCELLULAR LEVEL
 ACCRETIONARY - INCREASE INACCRETIONARY - INCREASE IN
INTERCELLULAR MATRIXINTERCELLULAR MATRIX
 MULTIPLICATIVE - HYPERPLASIAMULTIPLICATIVE - HYPERPLASIA
 DIMENSIONAL - HYPERTROPHYDIMENSIONAL - HYPERTROPHY
OR AUXETICOR AUXETIC

 THE MESENCHYME THAT GIVESTHE MESENCHYME THAT GIVES
RISE TO THE VAULT OFRISE TO THE VAULT OF
NEUROCRANIUM IS ARRANGEDNEUROCRANIUM IS ARRANGED
FIRST AS CAPSULAR MEMBRANEFIRST AS CAPSULAR MEMBRANE
AROUND THE DEVELOPING BRAIN.AROUND THE DEVELOPING BRAIN.

CAPSULAR MEMBRANECAPSULAR MEMBRANE
MEMBRANE
INNER ENDOMENIX OUTER ECTOMENIX
NUERAL CREST ORIGIN
MIXED PARAXIAL
MESODERM & NUERAL
CREST ORIGIN

ENDOMENIXENDOMENIX
ENDOMENIX
2 LEPTOMENINGEAL
COVERING OF
BRAIN
PIAMATTER ARACHNOID

ECTOMENIXECTOMENIX
ECTOMENIX
INNER DURA OUTER DURA

OSTEOGENESISOSTEOGENESIS
 ECTOMENIX FORMING SKULLECTOMENIX FORMING SKULL
VAULT IS – INTRAMEMBRANOUS.VAULT IS – INTRAMEMBRANOUS.
 ECTOMENIX FORMING FLOOR OFECTOMENIX FORMING FLOOR OF
BRAIN IS -- ENDOCHONDRAL.BRAIN IS -- ENDOCHONDRAL.

 SEVERAL PRIMARY AND SECONDARYSEVERAL PRIMARY AND SECONDARY
OSSIFICATION CENTRES DEVELOP INOSSIFICATION CENTRES DEVELOP IN
OUTER LAYER OF ECTOMENIX TO FORMOUTER LAYER OF ECTOMENIX TO FORM
INDIVIDUAL BONES.INDIVIDUAL BONES.
MESODERMALLY DERIVED ECTOMENIXMESODERMALLY DERIVED ECTOMENIX
GIVES RISE TO-GIVES RISE TO-
- FRONTAL BONE- FRONTAL BONE
- PARIETAL BONE- PARIETAL BONE
- SPHENOID BONE- SPHENOID BONE
- PETROUS TEMPORAL BONE- PETROUS TEMPORAL BONE
- OCCIPITAL BONE- OCCIPITAL BONE

 NUERAL CREST ORIGIN ECTOMENIXNUERAL CREST ORIGIN ECTOMENIX
GIVES RISE TOGIVES RISE TO
- LACRIMALBONE- LACRIMALBONE
- NASAL BONE- NASAL BONE
- SQUAMOUS TEMPORAL BONE- SQUAMOUS TEMPORAL BONE
- MAXILLARY BONE- MAXILLARY BONE
- MANDIBULAR BONE- MANDIBULAR BONE
- ZYGOMATIC BONE- ZYGOMATIC BONE

OCCIPITAL BONEOCCIPITAL BONE - 7- 7 centrescentres
 Supranuchal Squamous portion –Supranuchal Squamous portion –
2 intramembranous centres2 intramembranous centres
. ( 8. ( 8thth
week)week)
 Infranuchal squamous –Infranuchal squamous –
2 endochondral centres (102 endochondral centres (10thth
week)week)
 Basioccipital bone –Basioccipital bone –
1 endochondral centre (111 endochondral centre (11thth
week)week)
 Exoccipital bone – 2 endochondral centres

TEMPORAL BONETEMPORAL BONE -- 21 centres21 centres
 Squamous portion-1 intramembranous centreSquamous portion-1 intramembranous centre
(8 th week)(8 th week)
 Tympanic ring – 4 intramembranous centresTympanic ring – 4 intramembranous centres
(3 th month)(3 th month)
 Petrosal part – 14 endochondral centresPetrosal part – 14 endochondral centres
(16th week)(16th week)

ETHMOID BONEETHMOID BONE – 3 centres– 3 centres
Perpendicular plate & crista galli –Perpendicular plate & crista galli –
1 endochondral centre1 endochondral centre
Lateral labrynths in the nasalLateral labrynths in the nasal
cartilages - 2 endochondral centrescartilages - 2 endochondral centres

SPHENOID BONESPHENOID BONE – 19 centres– 19 centres
 Basisphenoid – 3 presphenoid &Basisphenoid – 3 presphenoid &
4 postsphenoid endochondral centres4 postsphenoid endochondral centres
 Greater wings – 2 centresGreater wings – 2 centres
 Lesser wings - 2 centresLesser wings - 2 centres
 Medial pterygoid plates –Medial pterygoid plates –
 Lateral pterygoid plates –Lateral pterygoid plates –
 Sphenoidal conchae – 2 endochondral centresSphenoidal conchae – 2 endochondral centres

 EARLIEST CENTRES OF OSSIFICATONEARLIEST CENTRES OF OSSIFICATON
FIRST APPEARS AT 7FIRST APPEARS AT 7THTH
AND 8AND 8THTH
WEEK POST CONCEPTION.WEEK POST CONCEPTION.
 THE MESENCHYME BETWEEN THETHE MESENCHYME BETWEEN THE
BONES DEVELOPS FIBERS TO FORMBONES DEVELOPS FIBERS TO FORM
SYNDESMOTIC ARTICULATIONS.SYNDESMOTIC ARTICULATIONS.
 MEMBRANOUS MESENCHYME FORMSMEMBRANOUS MESENCHYME FORMS
PERIOSTEUM.PERIOSTEUM.

FONTANELLESFONTANELLES
 AT BIRTH THE INDIVIDUAL CALVARIAL BONES AREAT BIRTH THE INDIVIDUAL CALVARIAL BONES ARE
SEPERATED BY SUTURE AND FONTANELLES.SEPERATED BY SUTURE AND FONTANELLES.
 ALSO CALLED AS “SOFT SPOTS”ALSO CALLED AS “SOFT SPOTS”
 SIX IN NUMBERSIX IN NUMBER
 ANTERIOR - BREGMA- CLOSES BY 18 MONTHS.ANTERIOR - BREGMA- CLOSES BY 18 MONTHS.
 POSTERIOR- LAMBDA- CLOSES BY 2 MONTHSPOSTERIOR- LAMBDA- CLOSES BY 2 MONTHS
 2 ANTEROLATERAL - PTERION- 3 MONTHS2 ANTEROLATERAL - PTERION- 3 MONTHS
 2POSTEROLATERAL - ASTERION- 2 YEARS.2POSTEROLATERAL - ASTERION- 2 YEARS.

FONTANELLESFONTANELLES

 THE PRECOCIOUS DEVELOPMENT OF BRAINTHE PRECOCIOUS DEVELOPMENT OF BRAIN
DETERMINES THE PREDOMINANE OF NUEROCRANIUMDETERMINES THE PREDOMINANE OF NUEROCRANIUM
OVER FACIAL PORTION.OVER FACIAL PORTION.
NUEROCRANIUM : FACENUEROCRANIUM : FACE
AT BIRTH 8 : 1AT BIRTH 8 : 1
22NDND
YEAR 6 : 1YEAR 6 : 1
55THTH
YEAR 4 : 1YEAR 4 : 1
ADULT 2 : 1 TO 2.5 : 1ADULT 2 : 1 TO 2.5 : 1
NEUROCRANIUMNEUROCRANIUM
AT BIRTH 25% OF ITS GROWTHAT BIRTH 25% OF ITS GROWTH
66THTH
MONTH 50%MONTH 50%
2 YEARS 75%2 YEARS 75%
10 YEARS 95%10 YEARS 95%
FACE- ONLY 65% AT 10 YEARS.FACE- ONLY 65% AT 10 YEARS.

CRANIAL BASECRANIAL BASE

 DURING THE LATE SOMITE PERIOD, THEDURING THE LATE SOMITE PERIOD, THE
OCCPITAL SCLEROTOMAL MESENCHYMEOCCPITAL SCLEROTOMAL MESENCHYME
CONCENTRATES AROUND THE NOTOCHORDCONCENTRATES AROUND THE NOTOCHORD
UNDERLYING THE DEVELOPING HINDBRAIN.UNDERLYING THE DEVELOPING HINDBRAIN.
 FROM THIS, MESENCHYMAL CONCENTRATIONSFROM THIS, MESENCHYMAL CONCENTRATIONS
EXTEND CEPHALYCALLY FORMING FLOOR OFEXTEND CEPHALYCALLY FORMING FLOOR OF
BRAIN.BRAIN.
 CONVERSION OF THE ECTOMENIXCONVERSION OF THE ECTOMENIX
MESENCHYME INTO CARTILAGE CONSTITUTESMESENCHYME INTO CARTILAGE CONSTITUTES
THE BEGINNING OF “CHONDROCRANIUM”,THE BEGINNING OF “CHONDROCRANIUM”,
STARTING ON 40STARTING ON 40THTH
DAY AFTER CONCEPTION.DAY AFTER CONCEPTION.

CHONDRIFICATION CENTRECHONDRIFICATION CENTRE
 PARACHORDAL CARTILAGE.PARACHORDAL CARTILAGE.
 HYPOPHYSIAL CARTILAGE.HYPOPHYSIAL CARTILAGE.
 BASISPHENOID CARTILAGE.BASISPHENOID CARTILAGE.
 PRESPHENOID CARTILAGE.PRESPHENOID CARTILAGE.
 ORBITOSPHENOID CARTILAGE.ORBITOSPHENOID CARTILAGE.
 ALISPHENOID CARTILAGE.ALISPHENOID CARTILAGE.
 CAPSULESCAPSULES
 -NASAL CAPSULE-NASAL CAPSULE
 -OTIC CAPSULE-OTIC CAPSULE

 PARACHORDAL CARTILAGE –PARACHORDAL CARTILAGE –
BOUNDARIES OF FORAMEN MAGNUMBOUNDARIES OF FORAMEN MAGNUM
BASILAR AND CONDYLAR PARTS OFBASILAR AND CONDYLAR PARTS OF
OCCIPITAL BONE.OCCIPITAL BONE.

 HYPOPHYSEAL CARTILAGEHYPOPHYSEAL CARTILAGE
GIVES BASISPHENOID CARTILAGEGIVES BASISPHENOID CARTILAGE
SELLA TURCICASELLA TURCICA
POSTERIOR PART OF BODY OFPOSTERIOR PART OF BODY OF
SPHENOIDSPHENOID

 PRESPHENOID CARTILAGEPRESPHENOID CARTILAGE
ANT. PART OF BODY OF SPHENOIDANT. PART OF BODY OF SPHENOID

 ORBITOSPHENOIDORBITOSPHENOID
LESSER WING OF SPHENOIDLESSER WING OF SPHENOID

 ALISPHENODALISPHENOD
GREATER WING OF SPHENOIDGREATER WING OF SPHENOID

 NASAL CAPSULENASAL CAPSULE
CARTILAGES OF NOSTRILCARTILAGES OF NOSTRIL
NASAL SEPTAL CARTILAGENASAL SEPTAL CARTILAGE
 OTIC CAPSULESOTIC CAPSULES
MASTOID AND PETROUS PART OFMASTOID AND PETROUS PART OF
TEMPORAL BONETEMPORAL BONE

CHONDRIFICATION CENTRESCHONDRIFICATION CENTRES

 BONE - SITE & NUMBER OFBONE - SITE & NUMBER OF
OSSIFICATION . . .OSSIFICATION . . .
CENTRECENTRE
INTRAMEMBRANOUS ENDOCHONDRALINTRAMEMBRANOUS ENDOCHONDRAL
 VOMER _ AlAE (2)VOMER _ AlAE (2)
 SPHENOID _ Medial pterygoid Presphenoid (3)SPHENOID _ Medial pterygoid Presphenoid (3)
plates (2) Postsphenoid (4)plates (2) Postsphenoid (4)
Lateral pterygoid Orbitosphenoid (2)Lateral pterygoid Orbitosphenoid (2)
plates (2) Alisphenoids (2)plates (2) Alisphenoids (2)
Pterygoid hamulus (2Pterygoid hamulus (2
Sphenoidal concha(2)Sphenoidal concha(2)
 INFERIOR NASAL Lamina (1)INFERIOR NASAL Lamina (1)
CONCHA _CONCHA _

PRIMORDIAL CARTILAGESPRIMORDIAL CARTILAGES

ANGULATIONANGULATION
 THE CENTRAL REGION OF THE CRANIAL BASE ISTHE CENTRAL REGION OF THE CRANIAL BASE IS
COMPOSED OF PRECHORDAL PARTS AND CHORDALCOMPOSED OF PRECHORDAL PARTS AND CHORDAL
THAT MEET AT AN ANGLE AT THE HYPOPHYSIALTHAT MEET AT AN ANGLE AT THE HYPOPHYSIAL
FOSSA.FOSSA.
 THE LOWER ANGLE, FORMED BY LINES FROMTHE LOWER ANGLE, FORMED BY LINES FROM
NASION TO SELLA TO BASION IN THE SAGITTALNASION TO SELLA TO BASION IN THE SAGITTAL
PLANE IS CRANIAL BASE ANGLEPLANE IS CRANIAL BASE ANGLE
 IT VARIES WITH THE STAGE OFIT VARIES WITH THE STAGE OF
 DEVELOPMENT ASDEVELOPMENT AS

 4 WEEK EMBRYO -154 WEEK EMBRYO -1500°°
 7 TO 8 WEEK EMBRYO -1307 TO 8 WEEK EMBRYO -130°°
 10 WEEKS EMBRYO -11510 WEEKS EMBRYO -115°°-120-120°°
 10-20 WEEKS -12510-20 WEEKS -125°°-130-130°°
THIS ANGULATION IS MAINTAINEDTHIS ANGULATION IS MAINTAINED
POSTNATALLY.POSTNATALLY.
- BETWEEN 6-10 WEEKS, THE WHOLE HEAD IS- BETWEEN 6-10 WEEKS, THE WHOLE HEAD IS
RAISED BY EXTENSION OF NECK , LIFTING THERAISED BY EXTENSION OF NECK , LIFTING THE
FACE FROM THE THORAX.FACE FROM THE THORAX.
THIS IS CONCOMITANT WITH PALATAL FUSION.THIS IS CONCOMITANT WITH PALATAL FUSION.www.indiandentalacademy.comwww.indiandentalacademy.com

ANGULATIONANGULATION

CRANIAL FLEXURECRANIAL FLEXURE

- CRANIAL BASE FLEXURE PLACES THE- CRANIAL BASE FLEXURE PLACES THE
FORAMEN MAGNUM DIRECTLY OVERFORAMEN MAGNUM DIRECTLY OVER
THE VERTICAL SPINAL CORDTHE VERTICAL SPINAL CORD
AND ACHIEVES A FORWARDAND ACHIEVES A FORWARD
ALIGNMENT OF THE FACE ANDALIGNMENT OF THE FACE AND
ORBITS BECAUSE OF HUMANORBITS BECAUSE OF HUMAN
BIPEDAL POSTURE.BIPEDAL POSTURE.
- GIVES WAY TO GROWING FACE.- GIVES WAY TO GROWING FACE.
- AFFECTS THE MANDIBULAR- AFFECTS THE MANDIBULAR
POSITIONING.POSITIONING.

POST NATAL GROWTHPOST NATAL GROWTH

3 MAJOR FACTORS IN DEVELOPENT OF3 MAJOR FACTORS IN DEVELOPENT OF
CRANIUM ARECRANIUM ARE
1.EXPANSION OF INTRACRANIAL1.EXPANSION OF INTRACRANIAL
CONTENT.CONTENT.
2.GROWTH OF SYNDESMOSIS (SUTURES).2.GROWTH OF SYNDESMOSIS (SUTURES).
3.SYNCHONDROSIS.3.SYNCHONDROSIS.

EXPANSION OFEXPANSION OF
INTRACRANIAL CONTENTINTRACRANIAL CONTENT
 In cranial development, the contentsIn cranial development, the contents
induce the container……………….induce the container……………….
J.Schowing, 1974J.Schowing, 1974

 GROWTH OF CRANIAL VAULT OCCURS PRIMARILY AS AGROWTH OF CRANIAL VAULT OCCURS PRIMARILY AS A
RESULT OF EXPANSION OF INTRACRANIAL CONTENT.RESULT OF EXPANSION OF INTRACRANIAL CONTENT.
 AS THE CRANIAL CONTENT EXPANDS IN SIZE, THEAS THE CRANIAL CONTENT EXPANDS IN SIZE, THE
CALVARIAL BONES, WHICH ARE ESSENTIALLYCALVARIAL BONES, WHICH ARE ESSENTIALLY FLOATINGFLOATING
UPON THE DURAMATER, ARE DISPLACED OUTWARDUPON THE DURAMATER, ARE DISPLACED OUTWARD
SEPERATIG THE BONES AT THERE SUTURAL MARGINS.SEPERATIG THE BONES AT THERE SUTURAL MARGINS.
 SUTURES RESPOND TO THIS SEPERATION (TENSION) BYSUTURES RESPOND TO THIS SEPERATION (TENSION) BY
OSTEOGENESIS , DEPOSITING BONE AT THE MARGINS OFOSTEOGENESIS , DEPOSITING BONE AT THE MARGINS OF
CALVARIAL BONE.CALVARIAL BONE.
 THE OUTER TABLES OF CALVARIA IS ASSOCIATED NOTTHE OUTER TABLES OF CALVARIA IS ASSOCIATED NOT
ONLY WITH INTRACRANIAL CONTENT, BUT ALSOWITHONLY WITH INTRACRANIAL CONTENT, BUT ALSOWITH
SOFT TISSUE ATTACHMENTS.SOFT TISSUE ATTACHMENTS.

SUTURESSUTURES
 In the closest union there is still some
separate existence of component parts ; in
the most complete separation there is some
reminiscence of union……

GROWTH OF SYNDESMOSISGROWTH OF SYNDESMOSIS
 SUTURS BEHAVE AS SPECIALLISED PERIOSTEMSUTURS BEHAVE AS SPECIALLISED PERIOSTEM
 SHOWS TENSION ADATED GROWTH, INSHOWS TENSION ADATED GROWTH, IN
RESPONSE TO GROWTH OF BRAIN AS WELL ASRESPONSE TO GROWTH OF BRAIN AS WELL AS
A RESULT OF MUSCLE FUNCTION.A RESULT OF MUSCLE FUNCTION.
 ON THE OTHER HAND, THE BONES OF THEON THE OTHER HAND, THE BONES OF THE
CRANIAL VAULT MUST REMAIN ARTICUALATEDCRANIAL VAULT MUST REMAIN ARTICUALATED
THROUGH SUTURES AND, HENCE, ARE OFTENTHROUGH SUTURES AND, HENCE, ARE OFTEN
EQUIPPPED WITH COMPLEX INTERDIGITATIONEQUIPPPED WITH COMPLEX INTERDIGITATION
THAT RESIST EXCESSIVE SEPERATION , WHILE ATTHAT RESIST EXCESSIVE SEPERATION , WHILE AT
THE SAME TIME PROVIDING EXTENSIVE SURFCETHE SAME TIME PROVIDING EXTENSIVE SURFCE
AREA FOR BONE GROWTH.AREA FOR BONE GROWTH.

 METOPIC SUTURES -7 YEARS.METOPIC SUTURES -7 YEARS.
 SAGITTALSAGITTAL
 CORONAL 20-40 YEARSCORONAL 20-40 YEARS
 LAMBDOIDALLAMBDOIDAL
 OCCIPITOMASTOIDOCCIPITOMASTOID
 SPHENOTEMPORAL 70 YEARSSPHENOTEMPORAL 70 YEARS
 SQUAMOUSSQUAMOUS

SYNCHONDROSISSYNCHONDROSIS
 ENDOCHONDRAL BONE JUNCTIONS SITES WHEREENDOCHONDRAL BONE JUNCTIONS SITES WHERE
CARTILAGE IS INTERPOSED BETWEEN CONTIGOUS BONESCARTILAGE IS INTERPOSED BETWEEN CONTIGOUS BONES
ARE KNOWN AS SYNCHONDROSIS.ARE KNOWN AS SYNCHONDROSIS.
 REMAINS OF CHONDROCRANIUM SEPERATING CENTRES OFREMAINS OF CHONDROCRANIUM SEPERATING CENTRES OF
OSSIFICATION.OSSIFICATION.
 PRESURE ADAPTED GROWTH.PRESURE ADAPTED GROWTH.
 POSTNATALLY, THERE ARE FOUR PRIMARY SYNCHONDROSESPOSTNATALLY, THERE ARE FOUR PRIMARY SYNCHONDROSES
1.SPHENOOCCIPITAL – 20-23 YEARS1.SPHENOOCCIPITAL – 20-23 YEARS
2.SPHENOETHMOID- 7 YEARS2.SPHENOETHMOID- 7 YEARS
3.INTERSPHENOID – DISAPPEARS AT BIRTH3.INTERSPHENOID – DISAPPEARS AT BIRTH
4.INTRAOCCIPITAL - 3-5 YEARS4.INTRAOCCIPITAL - 3-5 YEARS

 DURING ACTIVE GROWTH OFDURING ACTIVE GROWTH OF
SYCHONDROSES BOTH PRIMARYSYCHONDROSES BOTH PRIMARY
CENTRES OF OSIFICATION MOVECENTRES OF OSIFICATION MOVE
APART RELATIVE TO MIDDLE OF THEAPART RELATIVE TO MIDDLE OF THE
SYNCHONDROSIS.SYNCHONDROSIS.

SPHENOOCIPITALSPHENOOCIPITAL
SYNCHONDROSESSYNCHONDROSES
 SITUATED AT THE MIDPOINT OF CRANIAL BASE.SITUATED AT THE MIDPOINT OF CRANIAL BASE.
 EXCELLENT POSITION TO INFLUENCE DISPLACEMENT OF FACEEXCELLENT POSITION TO INFLUENCE DISPLACEMENT OF FACE
ANTERIORLY AND THE OCCIPITAL REGION POSTERIORLY.ANTERIORLY AND THE OCCIPITAL REGION POSTERIORLY.
 GREATER GROWTH ON OCCIPITAL ASPECT THAN ON ITS SPHENOIDALGREATER GROWTH ON OCCIPITAL ASPECT THAN ON ITS SPHENOIDAL
ASPECT.(SPERBER,1976).ASPECT.(SPERBER,1976).
 ACTIVE FOR VERY LONG.ACTIVE FOR VERY LONG.
 HYPOTHESIS ON GROWTH POTENTIAL OF SYNCHONDROSALHYPOTHESIS ON GROWTH POTENTIAL OF SYNCHONDROSAL
CARTILAGE MADE IT CLEAR THAT CERTAIN ENVIRONTAL FACTORSCARTILAGE MADE IT CLEAR THAT CERTAIN ENVIRONTAL FACTORS
,FOR eg PRESENCE AND MASS OF NUERAL TISSUE AND RELATIVE,FOR eg PRESENCE AND MASS OF NUERAL TISSUE AND RELATIVE
DEGREE OF COMPRESSIVE AND TENSILE FORCES DO INFLUENCE THEDEGREE OF COMPRESSIVE AND TENSILE FORCES DO INFLUENCE THE
SYNCHONDROSES.SYNCHONDROSES.
 PRIMARY DISPLACEMENT AND ENDOCHONDRAL BONE DEPOSITION.PRIMARY DISPLACEMENT AND ENDOCHONDRAL BONE DEPOSITION.

SYNCHONDROSISSYNCHONDROSIS

APPOSITIONAPPOSITION

HEAD CIRCUMFERENCEHEAD CIRCUMFERENCE
 AT MIDGESTATIONAL PERIOD- 18cmAT MIDGESTATIONAL PERIOD- 18cm
 AT BIRTH - 33cmAT BIRTH - 33cm
 1ST YEAR- 46cm1ST YEAR- 46cm
THEN SLOWS DOWNTHEN SLOWS DOWN
 2 YEAR- 49cm2 YEAR- 49cm
 3 YEARS- 50cm3 YEARS- 50cm
INCREASE BETWEEN 3 YEARS ANDINCREASE BETWEEN 3 YEARS AND
ADULTHOOD IS ONLY 6cmADULTHOOD IS ONLY 6cm

ANOMALIESANOMALIES
OFOF
DEVELOPMENTDEVELOPMENT

 ABSENCE OF HEAD -ACEPHALYABSENCE OF HEAD -ACEPHALY
 ABSENCE OF BRAIN -ANENCEPHALYABSENCE OF BRAIN -ANENCEPHALY
 ABSENCE OF SKULL –ACRANIAABSENCE OF SKULL –ACRANIA
 ROOFLESS SKULL -ACALVARIAROOFLESS SKULL -ACALVARIA
 FAILURE OF NORMAL CLEAVAGE OFFAILURE OF NORMAL CLEAVAGE OF
FOREBRAIN -HOLOPROSENCEPHALYFOREBRAIN -HOLOPROSENCEPHALY
 CYCLOPIA -SYNOPTHALMIACYCLOPIA -SYNOPTHALMIA

CRANIOSYNOSTOSISCRANIOSYNOSTOSIS
 PREMATURE CLOSURE OF CRANIAL SUTURES.PREMATURE CLOSURE OF CRANIAL SUTURES.
 DEPENDING ON WHICH SUTURE ARE PREMATURELYDEPENDING ON WHICH SUTURE ARE PREMATURELY
SYNOSTOSED.SYNOSTOSED.
 NORMOCEPHALYNORMOCEPHALY
 DOLICOCEPHALY- if the sagittal suture is involved, restriction inDOLICOCEPHALY- if the sagittal suture is involved, restriction in
lateral growth.lateral growth.
 BRACHICEPHALY- if the coronal suture is involved ,restriction inBRACHICEPHALY- if the coronal suture is involved ,restriction in
a-p direction.a-p direction.
 PLAGIOCEPHALY – assymetrical skull. Unilateral closure of coronal orPLAGIOCEPHALY – assymetrical skull. Unilateral closure of coronal or
lamboidal suture.lamboidal suture.

 TRIGONOCEPHALY- premature closure ofTRIGONOCEPHALY- premature closure of
metopic suture, triangular calvariametopic suture, triangular calvaria

 IN CONDITIONS LIKE CRETINISM ,IN CONDITIONS LIKE CRETINISM ,
PROGERIA, TRISOMY 21, ANDPROGERIA, TRISOMY 21, AND
CLEIDOCRANIAL DYSOSTOSIS THERECLEIDOCRANIAL DYSOSTOSIS THERE
IS DELAYED MIDLINE OSSIFICAIONIS DELAYED MIDLINE OSSIFICAION
OF FRONTAL AND SAGGITALOF FRONTAL AND SAGGITAL
SUTURES OF THE CALVARIA,SUTURES OF THE CALVARIA,
 ANTERIOR FONTANELLE MAYANTERIOR FONTANELLE MAY
REMAIN OPEN INTO ADULT LIFE.REMAIN OPEN INTO ADULT LIFE.

 ENCEPHOLOCELES-ENCEPHOLOCELES-
defects in closure of foramen caecum at thedefects in closure of foramen caecum at the
ethmoid frontal suture allowing herniationethmoid frontal suture allowing herniation
of the cranial contents into face.of the cranial contents into face.

 Affilicaton of cartilage growth produces aAffilicaton of cartilage growth produces a
reduced cranial base with increasedreduced cranial base with increased
angulation due to loss of flattening effect ofangulation due to loss of flattening effect of
sphenochondral synchondrosis.sphenochondral synchondrosis.
 Results in dished deformity of middle 1/3Results in dished deformity of middle 1/3rdrd
of facial skeleton accentuated by a bulgingof facial skeleton accentuated by a bulging
of nuerocranium.of nuerocranium.
 Seen inSeen in Achondroplasia, Cretinism andAchondroplasia, Cretinism and
Downs syndromeDowns syndrome

SYNDROMESSYNDROMES
 13 TRISOMY SYNDROME.13 TRISOMY SYNDROME.
EXTRA CHROMOSOMES 13.EXTRA CHROMOSOMES 13.
CLEFT LIP AND PALATECLEFT LIP AND PALATE
MICROCEPHALY WITH SEVERES BRAINMICROCEPHALY WITH SEVERES BRAIN
MALFORMATIONS.MALFORMATIONS.

 TRISOMY 18 SYNDROME (EDWARDSTRISOMY 18 SYNDROME (EDWARDS
SYNDROME)SYNDROME)
 PROMINENT LARGE FOREHEAD.PROMINENT LARGE FOREHEAD.

MAXILLAMAXILLA

GROSS ANATOMYGROSS ANATOMY
 FRONTAL PROCESSFRONTAL PROCESS
 ORBITAL SURFACEORBITAL SURFACE
 NASAL NOTCHNASAL NOTCH
 ANSANS
 ZYGOMATIC BONEZYGOMATIC BONE
 CANINE EMINENCECANINE EMINENCE
 ALVEOLAR PROCESSALVEOLAR PROCESS

PRENATAL GROWTHPRENATAL GROWTH

A one month embryo will have no real face, butA one month embryo will have no real face, but
the key primordia have already begun tothe key primordia have already begun to
gather, and this early swellings ,depressions,gather, and this early swellings ,depressions,
and thickenings are to undergo a series ofand thickenings are to undergo a series of
mergers and rearrangements that willmergers and rearrangements that will
transfer them from cluster of separate massestransfer them from cluster of separate masses
into a FACEinto a FACE

 At fourth week of of IUL-At fourth week of of IUL-
1.migration of neural crest cell.1.migration of neural crest cell.
2.formation of brachial arches2.formation of brachial arches

THE TWO PRINCIPAL SOURCES OF MESENCHYME IN HEAD ARETHE TWO PRINCIPAL SOURCES OF MESENCHYME IN HEAD ARE THETHE
PARAXIAL MESODERMPARAXIAL MESODERM && THE NEURAL CREST CELLS.THE NEURAL CREST CELLS.
CEPHALIC NEURAL CREST CELLS ARE PARTICULARILY IMPORTANT INCEPHALIC NEURAL CREST CELLS ARE PARTICULARILY IMPORTANT IN
THE FORMATION OF THE FACIAL PART OF THE SKULL.THE FORMATION OF THE FACIAL PART OF THE SKULL.
THESE CELLS MIGRATE BOTH IN FRONT & BEHIND THE DEVELOPINGTHESE CELLS MIGRATE BOTH IN FRONT & BEHIND THE DEVELOPING
EYE TO REACH THE PREDETERMINED SITESEYE TO REACH THE PREDETERMINED SITES FACIAL SWELLINGS.FACIAL SWELLINGS.
MIGRATION IS ASSITED BY HYALURONATE RICH FIBRONECTIN,MIGRATION IS ASSITED BY HYALURONATE RICH FIBRONECTIN,
COLLAGEN, CHONDRITIN SULFATE & GLYCOSAMINOGLYCANS.COLLAGEN, CHONDRITIN SULFATE & GLYCOSAMINOGLYCANS.
THE DISTRIBUTION & CONCENTRAION OF THESE PRODUCTS VARIESTHE DISTRIBUTION & CONCENTRAION OF THESE PRODUCTS VARIES
ALONG THE MIGRATION ROUTE.ALONG THE MIGRATION ROUTE.

 STOMODEUMSTOMODEUM
-INVAGINATION OR DIMPLE IN THE-INVAGINATION OR DIMPLE IN THE
SURFACE ECTODERM.SURFACE ECTODERM.
BUCCOPHARYNGEAL MEMBRANEBUCCOPHARYNGEAL MEMBRANE
RUPTURESRUPTURES
FOREGUT(PHARYNX)FOREGUT(PHARYNX)

 AT 4AT 4THTH
WEEKWEEK
-SEGMENTATION OF FUTURE FACE ,-SEGMENTATION OF FUTURE FACE ,
AND NECK REGION.AND NECK REGION.
PHARYNGEAL ARCHESPHARYNGEAL ARCHES
PHARYNGEAL POUCHESPHARYNGEAL POUCHES
PHARYNGEAL CLEFTSPHARYNGEAL CLEFTS

FIRST ARCH - MANDIBULAR ARCHFIRST ARCH - MANDIBULAR ARCH
BUD FOR MAXILLARY PROCESSBUD FOR MAXILLARY PROCESS

FACE AT 5TH WEEK IS ASFACE AT 5TH WEEK IS AS
THICK AS SHEET OF PAPER .THICK AS SHEET OF PAPER .
 2 SMALL RAISED2 SMALL RAISED
AREAS-NASALAREAS-NASAL
PLACODESPLACODES
 CENTRES DEEPENSCENTRES DEEPENS
TO FORM NASALTO FORM NASAL
PITSPITS
 BETWEEN NASALBETWEEN NASAL
PITS- MNPPITS- MNP
 LATERALLY -LNPLATERALLY -LNP

MNP MERGES IN THE MIDLINE TO FORM THE PRIMORDIA FORMNP MERGES IN THE MIDLINE TO FORM THE PRIMORDIA FOR
 MIDDLE PART OF NOSEMIDDLE PART OF NOSE
 PHILTRUMPHILTRUM
 PREMAXILLAPREMAXILLA
 PRIMARY PALATEPRIMARY PALATE
 LNP ENLARGES TO FORMLNP ENLARGES TO FORM
ALAE OF NOSEALAE OF NOSE
 LATERAL MERGING OF MAXILLARY ANDLATERAL MERGING OF MAXILLARY AND
MANDIBULAR PROCESS FORMS CHEEK.MANDIBULAR PROCESS FORMS CHEEK.

UPPER LIPUPPER LIP
 MNP +MAXILLARY PROCESSMNP +MAXILLARY PROCESS
 3 STAGES3 STAGES
 1.CONTACT OF TWO EPITHELIAL SHEETS.1.CONTACT OF TWO EPITHELIAL SHEETS.
 2.FUSION OF EPITHELIUM INTO SINGLE2.FUSION OF EPITHELIUM INTO SINGLE
SHEET.SHEET.
 3.DEGENERATION OF THIS SHEET,3.DEGENERATION OF THIS SHEET,
FOLLOWED BY INVASION OF THEFOLLOWED BY INVASION OF THE
CONNECTIVE TISSUE OF THE LIP GROWINGCONNECTIVE TISSUE OF THE LIP GROWING
THROUGH IT.THROUGH IT.

PALATEPALATE
 FORMATION OF PRIMARY ANDFORMATION OF PRIMARY AND
SECONDARY PALATE.SECONDARY PALATE.
 ELEVATION OF PALATAL SHELVES.ELEVATION OF PALATAL SHELVES.
 FUSION OF THE SHELVESFUSION OF THE SHELVES

PALATOGENESISPALATOGENESIS
5-12 WEEKS5-12 WEEKS
6-9 WEEKS IS CRITICAL6-9 WEEKS IS CRITICAL
PALATE
PRIMARY SECONDARY

FORMATION OF PALATEFORMATION OF PALATE
 THE STOMODEAL CHABER DIVIDES INTO ORAL AND NASALTHE STOMODEAL CHABER DIVIDES INTO ORAL AND NASAL
CAVITIES WHEN THE FRONTONASAL PROMINENCES DEVELOPCAVITIES WHEN THE FRONTONASAL PROMINENCES DEVELOP
HORIZONTAL EXTENSIONS INTO THE CHAMBER.HORIZONTAL EXTENSIONS INTO THE CHAMBER.
THESE EXTENSIONS FORMTHESE EXTENSIONS FORM
 CENTRAL PART OF UPPER LIP.CENTRAL PART OF UPPER LIP.
 PRIMARY PALATE FROM FRONTONASAL PROCESS.PRIMARY PALATE FROM FRONTONASAL PROCESS.
 TWO LATERAL SHELVES FROM MAXILLARY PROCESS.TWO LATERAL SHELVES FROM MAXILLARY PROCESS.
 TONGUE INTERVENSIONTONGUE INTERVENSION
WEDGE SHAPED PALATAL SHELVES GROW DOWNWARD INTOWEDGE SHAPED PALATAL SHELVES GROW DOWNWARD INTO
FLOOR OF MOUTH.FLOOR OF MOUTH.
 VERTICALLY ORIENTEDVERTICALLY ORIENTED

ELEVATION OF PALATALELEVATION OF PALATAL
SHELVESSHELVES
 CRITICAL STEP.CRITICAL STEP.
 6-9 WEEKS.6-9 WEEKS.
 CHANGE FROM VERTICAL POSITION FROMCHANGE FROM VERTICAL POSITION FROM
BESIDES THE TONGUE TO HORIZONTAL POSITIONSBESIDES THE TONGUE TO HORIZONTAL POSITIONS
OVERLYING THE TONGUE.OVERLYING THE TONGUE.
 INVOLVES MOVEMENT OF BOTH THE TONGUE ANDINVOLVES MOVEMENT OF BOTH THE TONGUE AND
PALATAL SHELVES.PALATAL SHELVES.
 AS THE SHELVES ROLL OVER THE TONGUE,THEAS THE SHELVES ROLL OVER THE TONGUE,THE
TONGUE MAY GLIDE ANTERIORLY TO OFFER LESSTONGUE MAY GLIDE ANTERIORLY TO OFFER LESS
RESISTANCE.RESISTANCE.
 PALATAL SHELVES MEET FIRST IN ANTERIORPALATAL SHELVES MEET FIRST IN ANTERIOR
REGION WHERE THEY UNITE WITH PRIMARYREGION WHERE THEY UNITE WITH PRIMARY
PALATE AND NASAL SEPTUM.PALATE AND NASAL SEPTUM.

REASON FOR ELEVATIONREASON FOR ELEVATION
OF SHELVES AND THEIROF SHELVES AND THEIR
CONTROVERSYCONTROVERSY
 RELATIONSHIP BETWEEN INCREASED VENTRAL GROWTH OFRELATIONSHIP BETWEEN INCREASED VENTRAL GROWTH OF
MANDIBLE, DISPLACEMENT OF TONGUE, AND PALATAL ELEVATIONMANDIBLE, DISPLACEMENT OF TONGUE, AND PALATAL ELEVATION
NOT CLEAR.NOT CLEAR.
 ROLE OF MUSCULAR ACTIVITY AND CERVICAL FLEXIONROLE OF MUSCULAR ACTIVITY AND CERVICAL FLEXION
PROPOSED.PROPOSED.
 INTRINSIC MECHANISM BY WHICH PALATAL SHELVES BECOMEINTRINSIC MECHANISM BY WHICH PALATAL SHELVES BECOME
REORIENTED.REORIENTED.
 3 BASIC FACTORS3 BASIC FACTORS
 1.CONTRACTILE ELEMENTS WITHIN THE SHELVES.1.CONTRACTILE ELEMENTS WITHIN THE SHELVES.
 2.CHANGES IN EXTRACELLULAR MATRIX. (2.CHANGES IN EXTRACELLULAR MATRIX. (INTRINSIC SHELF FORCE)INTRINSIC SHELF FORCE)
. -GEL FIBRE NETWORK.. -GEL FIBRE NETWORK.
 3.CHANGES IN EPITELIAL CELL ADHESIVITY AND TRACTION.3.CHANGES IN EPITELIAL CELL ADHESIVITY AND TRACTION.

SHIFT IN CIRCULATIONSHIFT IN CIRCULATION
 IMPORTANT SHIFT IN CIRCULATIONIMPORTANT SHIFT IN CIRCULATION
IN THIS REGION DURING CRITICALIN THIS REGION DURING CRITICAL
TIME PERIOD OF 7-8 WEEK.TIME PERIOD OF 7-8 WEEK.
 6TH WEEK –STAPEDIAL ARTERY –ICA.6TH WEEK –STAPEDIAL ARTERY –ICA.
 7THWEEK –STAPEDIAL ARTERY7THWEEK –STAPEDIAL ARTERY
SEVERES ITS CONTACT WITH ICA.SEVERES ITS CONTACT WITH ICA.
 SAME TIME ITS BRANCHES TOSAME TIME ITS BRANCHES TO
MAXIILLA AND MANDIBLE GETSMAXIILLA AND MANDIBLE GETS
ATTACHED TO ECA.ATTACHED TO ECA.
ICA ECAwww.indiandentalacademy.comwww.indiandentalacademy.com

CHANGE IN BLOOD SPPLYCHANGE IN BLOOD SPPLY
OF FACE DURING 7TH WEEKOF FACE DURING 7TH WEEK

FUSION OF PALATALFUSION OF PALATAL
SHELVESSHELVES
 9-10 WEEK.9-10 WEEK.
 EPETHLIUM THICKENS AND CONTACTS.EPETHLIUM THICKENS AND CONTACTS.
 ROLE OF GLYCOPROTEINS AND DESMOSOMESROLE OF GLYCOPROTEINS AND DESMOSOMES
 DEGENERATION OF EPITHELIUM.DEGENERATION OF EPITHELIUM.
 CONECTIVE TISSUE PENETRATION AND INTERMINGLING.CONECTIVE TISSUE PENETRATION AND INTERMINGLING.
 ENTIRE PALATE DOES NOT FUSE AT SAME TIME, INTIALENTIRE PALATE DOES NOT FUSE AT SAME TIME, INTIAL
CONTACT ,CENTRL REGION OF SECONDARY PALATE, THENCONTACT ,CENTRL REGION OF SECONDARY PALATE, THEN
CLOSURE CONTINUES BOTH ANT. AND POSTERIORLY.CLOSURE CONTINUES BOTH ANT. AND POSTERIORLY.

FUSIONFUSION

OSSIFICATION CENTREOSSIFICATION CENTRE
FORFOR
MAXILLAMAXILLA
 PRIMARY CENTRE-PRIMARY CENTRE-
 7TH WEEK7TH WEEK
 AT TERMINATION OF INFRAORBITALAT TERMINATION OF INFRAORBITAL
NERVE.NERVE.
 SECONDARY CENTRE-SECONDARY CENTRE-
 ZYGOMATIC.ZYGOMATIC.
 ORBITONASALORBITONASAL
 NASOPALATINE.NASOPALATINE.
 INTERMAXILLARY.INTERMAXILLARY.

POST NATAL GROWTHPOST NATAL GROWTH
CAN BE EXPLAINED BYCAN BE EXPLAINED BY
 SURFACE APPOSITION.SURFACE APPOSITION.
 SUTURAL HYPOTHESISSUTURAL HYPOTHESIS
 NASAL SEPTUM.NASAL SEPTUM.
 LACRIMAL SUTURELACRIMAL SUTURE
 MAXILLARY TUBEROSITYMAXILLARY TUBEROSITY
 KEY RIDGEKEY RIDGE
 FUNCTIONAL MATRIX THEORYFUNCTIONAL MATRIX THEORY

SURFACE APPOSITIONSURFACE APPOSITION

SURFACE APPOSITION OFSURFACE APPOSITION OF
MAXILLARY TUBEROSITYMAXILLARY TUBEROSITY
AREAAREA

ZYGOMATIC REGIONZYGOMATIC REGION
 POSTERIORPOSTERIOR
SURFACE-SURFACE-
DEPOSITORY.DEPOSITORY.
 ANTERIOR-ANTERIOR-
RESORPTIVERESORPTIVE
-POSTERIORLY.-POSTERIORLY.
 LATERAL SIDE-LATERAL SIDE-
DEPOSITIONDEPOSITION
 MEDIALMEDIAL
RESORPTION-RESORPTION-
LATERALLYLATERALLY

SURFACE APPOSITION INSURFACE APPOSITION IN
ALVEOLAR SURFACEALVEOLAR SURFACE

PRIMARY DISPLACEMENTPRIMARY DISPLACEMENT

SECONDARY DISPLACEMENTSECONDARY DISPLACEMENT

SUTURAL THEORYSUTURAL THEORY
 STATES THAT THE DISPLACEMANT OFSTATES THAT THE DISPLACEMANT OF
MAXILLARY COMPLEX IS DUE TOMAXILLARY COMPLEX IS DUE TO
PRIMARY GROWTH AT CIRCUMMAXILLARYPRIMARY GROWTH AT CIRCUMMAXILLARY
SUTURES.SUTURES.
 CENTRE OF PRIMARY GROWTH.CENTRE OF PRIMARY GROWTH.
 DEMONSTRATED TO BE SITE OFDEMONSTRATED TO BE SITE OF
SECONDARY ,COMPENSATORY BONESECONDARY ,COMPENSATORY BONE
GROWTH PRIMARILY RESPONSIVE TOGROWTH PRIMARILY RESPONSIVE TO
EXTRINSIC ENVIRONMENTAL FACTORS.EXTRINSIC ENVIRONMENTAL FACTORS.

SUTURE SYSTEMSUTURE SYSTEM
 THE MIDFACE IS CONNECTED TOTHE MIDFACE IS CONNECTED TO
NUEROCRANIUM BY ANUEROCRANIUM BY A
CIRCUMMAXILLARY SUTURECIRCUMMAXILLARY SUTURE
SYSTEM.SYSTEM.
 SAGITTAL SUTURE STSTEMSAGITTAL SUTURE STSTEM
COMPRISES OFCOMPRISES OF
-MIDPALATAL-MIDPALATAL
-INTERMAXILLARY-INTERMAXILLARY
-INTERNASAL-INTERNASAL

NASAL SEPTUM HYPOTHESISNASAL SEPTUM HYPOTHESIS
 NATURE OF THE TISSUE.NATURE OF THE TISSUE.
 EFFECT OF REMOVAL OF NASALEFFECT OF REMOVAL OF NASAL
SEPTUM.SEPTUM.

NATURE OF TISSUENATURE OF TISSUE
 HYALINE CARTILAGEHYALINE CARTILAGE
 CAPABLE OF TISSUE SEPERATINGCAPABLE OF TISSUE SEPERATING
GROWTH.GROWTH.
 PART OF CARTILAGENOUS CRANIALPART OF CARTILAGENOUS CRANIAL
BASE.BASE.

ON REMOVALON REMOVAL
 MIDFACIAL GROWTH IS DEFICIENT A-PMIDFACIAL GROWTH IS DEFICIENT A-P
AND TO LESSER EXTENT,VERTICALLY.AND TO LESSER EXTENT,VERTICALLY.
 30% DECREASE AT PREMAXILLO-30% DECREASE AT PREMAXILLO-
MAXILLARY SUTURE.MAXILLARY SUTURE.
 SLIGHT DECREASE IN GROWTH ATSLIGHT DECREASE IN GROWTH AT
MAXILLO PALATAL SUTURE.MAXILLO PALATAL SUTURE.
 IMPORTANT BUT NOT DETERMINING.IMPORTANT BUT NOT DETERMINING.

TWO MECHANISMSTWO MECHANISMS
 INTERSTITIAL CARTILAGINOUSINTERSTITIAL CARTILAGINOUS
GROWTH WITHIN THE NASAL SEPTUMGROWTH WITHIN THE NASAL SEPTUM
PUSHES THE MIDFACE DOWNWARDPUSHES THE MIDFACE DOWNWARD
AND FORWARD RELATIVE TOAND FORWARD RELATIVE TO
CRANIAL BASE WITHCRANIAL BASE WITH
CIRCUMAXILLARY SUTURES FILLINGCIRCUMAXILLARY SUTURES FILLING
IN.IN.
(SCOTT,1953)(SCOTT,1953)

 22NDND
HYPOTHESIS IDENTIFIEDHYPOTHESIS IDENTIFIED
SEPTOPREMAXILLARY LIGAMENT.SEPTOPREMAXILLARY LIGAMENT.
 THOUGHT TO PROVIDE A MEANS FORTHOUGHT TO PROVIDE A MEANS FOR
THE GROWTH OF NASAL SEPTUM TOTHE GROWTH OF NASAL SEPTUM TO
BE TRANSLATED INTO A TRACTION,BE TRANSLATED INTO A TRACTION,
OR A PULL, RATHER THAN PUSH.OR A PULL, RATHER THAN PUSH.
(LATHAM 1970)(LATHAM 1970)

FUNCTIONAL MATRIXFUNCTIONAL MATRIX
HYPOTHESISHYPOTHESIS
 THE FUNCTIONAL MATRIX HYPOTHESISTHE FUNCTIONAL MATRIX HYPOTHESIS
EXPLICITLY CLAIMS THAT THE ORIGIN ,EXPLICITLY CLAIMS THAT THE ORIGIN ,
GROWTH AND MAINTAINENCE OF ALLGROWTH AND MAINTAINENCE OF ALL
SKELETAL TISSUE AND ORGANS ARESKELETAL TISSUE AND ORGANS ARE
ALWAYS SECONDARY, COMPENSATORY ANDALWAYS SECONDARY, COMPENSATORY AND
OBLIGATORY RESPONSE TO TEMPORALLYOBLIGATORY RESPONSE TO TEMPORALLY
AND OPERATIONALLY PRIOR EVENTS ORAND OPERATIONALLY PRIOR EVENTS OR
PROCESSES THAT OCCUR IN SPECIFICALLYPROCESSES THAT OCCUR IN SPECIFICALLY
RELATED NONSKELETAL TISSUES , ORGANSRELATED NONSKELETAL TISSUES , ORGANS
OR FUNCTIONING SPACES.OR FUNCTIONING SPACES.
(MOSS,1981)(MOSS,1981)

 STATES THAT FACE IS NOT ONLYSTATES THAT FACE IS NOT ONLY
COMPRISED OF FUNCTIONALCOMPRISED OF FUNCTIONAL
COMPONENTS, BUT IT IS ALSO COMPRISEDCOMPONENTS, BUT IT IS ALSO COMPRISED
OF NUMBER OF FUNCTIONING SPACES –OF NUMBER OF FUNCTIONING SPACES –
THE NASAL ,THE PHARYNGEAL, AND ORALTHE NASAL ,THE PHARYNGEAL, AND ORAL
–WHICH TOGETHER FORM THE–WHICH TOGETHER FORM THE OROFACIALOROFACIAL
CAPSULAR MATRIX.CAPSULAR MATRIX.
 ““EPIGENIC”EPIGENIC” GOVERNING DETERMINANT .GOVERNING DETERMINANT .

SKELETAL UNIT FUNCTIONALSKELETAL UNIT FUNCTIONAL
..
MATRIXMATRIX
 BASAL BODY INFRAORBITALBASAL BODY INFRAORBITAL
NERVENERVE
 ORBITAL UNIT EYEBALLORBITAL UNIT EYEBALL
 NASAL UNIT SEPTAL CARTILAGENASAL UNIT SEPTAL CARTILAGE
 ALVEOLAR UNIT TEETHALVEOLAR UNIT TEETH

MAXILLARY TUBEROSITYMAXILLARY TUBEROSITY
 DEPOSITION ALONGDEPOSITION ALONG
THE POSTERIORTHE POSTERIOR
MARGIN.MARGIN.
 ENDOSTEAL SIDE OFENDOSTEAL SIDE OF
CORTEX-CORTEX-
RESORPTIVE.RESORPTIVE.
 POSTERIOR ANDPOSTERIOR AND
LATERALLATERAL
MOVEMENT.MOVEMENT.

KEY RIDGEKEY RIDGE
 VERTICAL CRESTVERTICAL CREST
JUST BELOWJUST BELOW
MALARMALAR
PROTUBERANCE.PROTUBERANCE.
 FIXED REFERANCEFIXED REFERANCE
POINT.POINT.

V PRINCIPAL OF ENLOWS ANDV PRINCIPAL OF ENLOWS AND
BANGBANG

 Growth in height verticalGrowth in height vertical
 Growth in width transverseGrowth in width transverse
 Growth in length A - PGrowth in length A - P

WIDTHWIDTH
 GROWTH OF MIDPALATINE SUTURE.GROWTH OF MIDPALATINE SUTURE.
 REMODELLING OF LATERAL SURFACEREMODELLING OF LATERAL SURFACE
OF ALVEOLAR PROCESS.OF ALVEOLAR PROCESS.
 MUTUAL TRANSVERSE ROTATIONMUTUAL TRANSVERSE ROTATION
GIVES PALATE “U” SHAPE.GIVES PALATE “U” SHAPE.

LENGTHLENGTH
Maxillary
tuberosity
Palato -
maxillary
suture
primary secondary
displacement

POST NATALPOST NATAL
 AT BIRTHAT BIRTH
HARD PALATE- LENGTH = WIDTHHARD PALATE- LENGTH = WIDTH
 1-2 YEAR1-2 YEAR
-EXTENSIVE REMODELLING-EXTENSIVE REMODELLING
DESCENT OF PALATEDESCENT OF PALATE
ENLARGEMENT OF NASAL CAVITYENLARGEMENT OF NASAL CAVITY
MIDPALATINE GROWTH CEASES BUTMIDPALATINE GROWTH CEASES BUT
NO SYNOSTOSIS.NO SYNOSTOSIS.

MIXED DENTIONMIXED DENTION
 GROWTH IN WIDTH OF ARCH ANTERIORGROWTH IN WIDTH OF ARCH ANTERIOR
TO 1TO 1STST
MOLAR CEASES BY 5-6 YEARS.MOLAR CEASES BY 5-6 YEARS.
 INTERCANINE WIDTH IS COMPLETED BY 12INTERCANINE WIDTH IS COMPLETED BY 12
YEARS IN FEMALES AND 18 YEARS INYEARS IN FEMALES AND 18 YEARS IN
MALES.MALES.
 MIDPALATINE SUTURE STARTS CLOSINGMIDPALATINE SUTURE STARTS CLOSING
BY 9-10 YEARS.BY 9-10 YEARS.
 THERFORE RME CAN BE BEST DONE ATTHERFORE RME CAN BE BEST DONE AT
9-14 YEARS.9-14 YEARS.

77THTH
YEAR –A BENCHMARKYEAR –A BENCHMARK
 GROWTH OF CNS, BRAIN AND EYEGROWTH OF CNS, BRAIN AND EYE
ESSENTIALLY COMPLETED.ESSENTIALLY COMPLETED.
 SPHENOETHMOIDALSPHENOETHMOIDAL
SYNCHONDROSES FUSES AT ABOUTSYNCHONDROSES FUSES AT ABOUT
THE TIME ESTABLISHING ATHE TIME ESTABLISHING A
RELATINELY STABLE ANTERIORRELATINELY STABLE ANTERIOR
CRANIAL BASE.CRANIAL BASE.
 NASAL CAPSULE OSSIFIES.NASAL CAPSULE OSSIFIES.

DEVELOPMENTALDEVELOPMENTAL
DISTURBANCES AFFECTINGDISTURBANCES AFFECTING
MAXILLAMAXILLA Cleft palate.Cleft palate.
 Micrognathia.Micrognathia.
 Macrognathia.Macrognathia.
 Treacher collins syndrome.Treacher collins syndrome.
 Cleidocranial dysostosis.Cleidocranial dysostosis.
 Crouzons syndrome.Crouzons syndrome.
 Apert syndrome.Apert syndrome.
 AchondroplasiaAchondroplasia..

CLEFT LIP AND PALATECLEFT LIP AND PALATE
 DEVELOPS DUE TO NON FUSION OFDEVELOPS DUE TO NON FUSION OF
 CLEFT LIP -FNP +MAXILLARY PROCESSCLEFT LIP -FNP +MAXILLARY PROCESS
 CLP -MNP+MAXILLARY PROCESSCLP -MNP+MAXILLARY PROCESS
 MIDLINE CLEFT OF UPPER LIPMIDLINE CLEFT OF UPPER LIP
-FNP (lowest part)-FNP (lowest part)
OBLIQUE FACIAL CLEFTOBLIQUE FACIAL CLEFT
-MAX. PROCESS + LNP-MAX. PROCESS + LNP
LATERAL FACIAL CLEFTLATERAL FACIAL CLEFT
-UNILATERAL NON FUSION OF MAX+MAND PROCESS-UNILATERAL NON FUSION OF MAX+MAND PROCESS

CLEFT LIP AND CLEFTCLEFT LIP AND CLEFT
PALATEPALATE

 CLEFT PALATE DUECLEFT PALATE DUE
TO NON FUSION OFTO NON FUSION OF
LATERAL PALATINELATERAL PALATINE
PROCESS.PROCESS.

 MACROSTOMIA –MAXILLARYMACROSTOMIA –MAXILLARY
. +MANDIBULAR. +MANDIBULAR
PROCESSPROCESS
 MICROSTOMIA – TOO MUCH FUSIONMICROSTOMIA – TOO MUCH FUSION
OF MAXILLARY + MANDIBULAROF MAXILLARY + MANDIBULAR
PROCESSPROCESS

TREACHER COLLINSTREACHER COLLINS
SYNDROMESYNDROME
 ALSO CALLED AS MANDIBULOFACIALALSO CALLED AS MANDIBULOFACIAL
DYSOSTOSIS.DYSOSTOSIS.
 DUE TO UNDERDEVELOPMENT OF 1DUE TO UNDERDEVELOPMENT OF 1STST
ARCH,ARCH,
MAX. MESODERM AT AND AFTER 2 MTSMAX. MESODERM AT AND AFTER 2 MTS
OF I.U LIFE NOT DEVELOPED.OF I.U LIFE NOT DEVELOPED.
 HYPOPLASTIC MALAR AND MANDIBLEHYPOPLASTIC MALAR AND MANDIBLE
BONE.BONE.
 MACROSTOMIA, HIGH ARCHED PALATE.MACROSTOMIA, HIGH ARCHED PALATE.

ACHONDROPLASIAACHONDROPLASIA
 RETARDED MAXILLARY GROWTH.RETARDED MAXILLARY GROWTH.
 ENLARGED CALVARIA.ENLARGED CALVARIA.
 FRONTAL BOSSING.FRONTAL BOSSING.
 DISTURBED ENDOCHONDRAL BONEDISTURBED ENDOCHONDRAL BONE
FORMATION.FORMATION.
 SHORT UPPER FACIAL HEIGHT.SHORT UPPER FACIAL HEIGHT.

CLEIDOCRANIAL DYSOSTOSISCLEIDOCRANIAL DYSOSTOSIS
 OPEN FONTANELLESOPEN FONTANELLES
 SUNKEN SAGITTAL SUTURESUNKEN SAGITTAL SUTURE
 UNDERDEVLOPED MAXILLAUNDERDEVLOPED MAXILLA
 NARROW PALATENARROW PALATE

APERT SYNDROME:
 IS A SINGLE GENE DISORDER,
CHARACTERIZED BY PREMATURE
FUSION OF CRANIAL SUTURES,
 BIZARRE CRANIOFACIAL
APPEARANCE,
 HIGHLY ARCHED PALATE,
 SYNDACTYLY (FUSION OF DIGITS)
 CONGENITAL HEART DEFECTS

CROUZAN SYNDROMECROUZAN SYNDROME
 SAME AS APERT SYNDROME BUTSAME AS APERT SYNDROME BUT
WITHOUT SYNDACTYLYWITHOUT SYNDACTYLY
 TRIANGULAR FRONTAL DEFECT.TRIANGULAR FRONTAL DEFECT.

CONCLUSIONCONCLUSION
JUST AS THE CLINICIAN NEEDS THE MEDICALJUST AS THE CLINICIAN NEEDS THE MEDICAL
HISTORY TO MAKE A LOGICAL DIAGNOSIS, SO TOOHISTORY TO MAKE A LOGICAL DIAGNOSIS, SO TOO
THE GROWTH AND DEVELOPMENT OF FACE ISTHE GROWTH AND DEVELOPMENT OF FACE IS
ESSENTIAL FOR A LOGICAL EXPLANATION OF ANYESSENTIAL FOR A LOGICAL EXPLANATION OF ANY
STRUCTURAL AND FUNCTIONAL IMBALANCES IF ITSTRUCTURAL AND FUNCTIONAL IMBALANCES IF IT
DO OCCURSDO OCCURS..

REFERANCESREFERANCES
 Essentials of facial growth –DONALD H . ENLOWEssentials of facial growth –DONALD H . ENLOW

 Craniofacial development - SPERBERCraniofacial development - SPERBER
 Handbook of orthodontics - ROBERT E.Handbook of orthodontics - ROBERT E.
 MOYERSMOYERS
 Introduction to craniofacial biology- DAVID S.CARLSONIntroduction to craniofacial biology- DAVID S.CARLSON
..
 . -SALZMAN. -SALZMAN
 Oral pathology -SHAFERSOral pathology -SHAFERS
 GRAYS ANATOMYGRAYS ANATOMY
 -McDONALD-McDONALD
 Human anatomy colour atlas –McMINN AND HUTCHINGSHuman anatomy colour atlas –McMINN AND HUTCHINGS

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