Skull is complicated bony structure.Skull protects our Brain and special sensory organs like vision,taste,hearing etc
The only movable joint in Skull is Temporomandibular joint.other bones connect each other by fibrous joint(Suture)
Skull divide into two parts
1:Neurocranium contains brain
2:Viscero cranium Skeleton of face
Neurocranium(calvaria) consist 8 bones that protect the brain :it contains 4 single bones and two paired bones
Single bones are Frontal,Ethmoid,Sphenoid and Occipital
Paired bones are Parietal and Temporal
Viscero cranium contains 14 bones
6 paired bones are maxilla,nasal,lacrimal,zygomatic,palatine and inferior concha
2 single bones are Mandible and vomer
largest bone of facial skeleton is Mandible
there are total 22 bones in the structure of skull
Three pairs of middle ear bones can also be added
total 22+6 =28 bones form skull
i will expalin each bone in detail lets start with first bone
1 FRONTAL BONE
This bone is middle and single.it participate in Anterior view,roof of orbit and nasal cavity
This bone consist of two parts Horizontal and perpendicular
1 Horizontal or orbital plate.This plate made of two halves .between them is notch called Ethmoidal notch.This notch houses ethmoidal Horizontal plate (cribiform plate)
Horizontal plate has two surfaces .orbital(inferior) and cranial(Superior)
There is a depression in anterolateral part of orbital surface for housing lacrimal gland called Fossa Lacrimal
In superior surface have depression for cerebral gyri called digital impressions
Posterior border of frontal bone articulate with anterior border of small wing of spheniod bone
2 Perpendicualar or squamous part
It has two surfaces anterior and posterior
Anterior parts
This surface has frontal eminence which is more prominent in females.
Glabella is present between two supercialiary arches
Superciliary arch is due to frontal sinus
Nasal portion present below glabella for articulation with nasal ,maxilla,and lacrimal bones .in the middle of Nasal portion has Nasal spine that articulate with ethmoid bone
Posterior parts
Frontal crest is present in middle surface.in its inferior surface has edges that create foramen caecum with ethmoid bone
In Superior end it has sulcus for housing frontal sinus called sagittal sinus
It also has digital impressions for housing cerebral gyri
Posterior border of perpendicular plate artiwith parietal bones create coronal suture.
