TTHE HE SSKULLKULL

Panjit ChunhabunditPanjit Chunhabundit, Ph.D., Ph.D.Department of Anatomy, Faculty of Dentistry, Department of Anatomy, Faculty of Dentistry, MahidolMahidol UniversityUniversity

DTAN 601 and DTAN 711DTAN 601 and DTAN 711

IINTRODUCTIONNTRODUCTION

DDEVELOPMENT EVELOPMENT OOF F TTHE HE SSKULLKULL

““IntramembranousIntramembranous ossificationossification””

““EndochondralEndochondral ossificationossification””

NeurocraniumNeurocranium

ViscerocraniumViscerocranium

Development ofDevelopment of NeurocraniumNeurocraniumCartilagenousCartilagenous NC.:NC.: base of skullbase of skull

Membranous NC.:Membranous NC.: frontal & parietal bonesfrontal & parietal bones

Development ofDevelopment of ViscerocraniumViscerocraniumCartilagenousCartilagenous VC.:VC.: malleusmalleus, , incusincus, stapes,, stapes,

styoidstyoid processprocessMembranous VC.:Membranous VC.: maxilla, maxilla, zygomaticzygomatic,, squamous squamous

temporal bone, mandibletemporal bone, mandible

FontanelleFontanelle

-- AnteriorAnterior

-- PosteriorPosterior

-- AnterolateralAnterolateral((sphenoidalsphenoidal))

-- PosterolateralPosterolateral(mastoid)(mastoid)

The Vault of the SkullThe Vault of the Skull((ClavariaClavaria))

- Frontal bone“metopic suture”

- Parietal bone

- Squamous part of temporal

bone

- Occipital bone

“Pterion”

The Base of the SkullThe Base of the Skull

Anterior cranial Anterior cranial fossafossa-- Orbital plate of frontal boneOrbital plate of frontal bone-- CribiformCribiform plate ofplate of ethmoidethmoid bonebone-- Lesser wing of sphenoid boneLesser wing of sphenoid bone

““contain frontal lobecontain frontal lobe””

Middle cranial Middle cranial fossafossa- Lesser wing of sphenoid bone- Temporal bone- Petrous part of temporal bone““contain temporal lobe & pituitarycontain temporal lobe & pituitary””

Posterior cranial Posterior cranial fossafossa-- PetrousPetrous part of temporal bonepart of temporal bone-- Occipital boneOccipital bone

““contain cerebellumcontain cerebellum””

ViscerocraniumViscerocranium(Facial skeleton)(Facial skeleton)

-- compose of 14 pieces of bonescompose of 14 pieces of bones-- fragile & light weightfragile & light weight

The Newborn SkullThe Newborn Skull-- the brain reach 25% of its adult size at birththe brain reach 25% of its adult size at birth-- reach 75% by the age of 4 yrsreach 75% by the age of 4 yrs-- has relatively small size of facehas relatively small size of face-- the nasal cavity is largely between the orbitsthe nasal cavity is largely between the orbits-- many separate parts of bones of base of skull many separate parts of bones of base of skull

still united with cartilagestill united with cartilage

Skull MalformationsSkull MalformationsAcraniaAcrania or or CranioschisisCranioschisis

CraniosynostosisCraniosynostosis or or CraniostenosisCraniostenosis

ScaphocephalyScaphocephaly OxycephalyOxycephaly

The EndThe Endhttp://www.http://www.dtdt..mahidolmahidol.ac..ac.thth//wwwrootwwwroot//anatomyanatomy.html.html