The face is formed by 13 bones in addition to frontal bone and fuse before birth.
Zygomatic bones -2
Each zygomatic bone start as 2 bones in embryonic stage
It is form cheek prominence.
It is form part of the floor and lateral wall of the orbital cavity.
MAXILLA -1 OR UPPER JAW
Maxilla also starts as 2 bones in embryonic stage and fuse before birth.
It is forms the upper jaw
It is also form anterior part of the roof of the mouth.
It is form lateral wall of the nasal cavity
It is form part of the floor of the orbital cavities .
There is one upper alveolar ridge in maxilla which carries the upper teeth.
There is sinuses present in maxilla called maxillary sinus.it is the largest sinus and this sinus lined with ciliated mucous membranes which propel mucus towards nose because there is connection or opening inbetween sinus and nasal cavity.
NASAL BONES -2
Two small flat bones present on the nose and form lateral wall of the nose and bridge of the nose .
LACRIMAL BONES -2
These are two small bones presents lateral to the nasal bones and form medial wall of the eye socket and orbital cavity.
Inside Lacrimal bones there is tiny hole .and through this hole nasolacrimal duct passes.
This nasolacrimal duct carry tear from medial canthus (Inner corner)of the eye to nasal cavity.
VOMER -1
It is a small flat bone inside the nose .
It separate the two nostril and form septum of the nasal cavity.
It is form lower part of nasal septum.
PALATINE BONES-2
These are two small , L shaped bones l
These bones are help in formation of hard palate ,Nasal cavity and eye socket.
INFERIOR CONCHAE.
There are three types of conchae in nasal cavity
Superior conchae
Middle conchae
Inferior conchae
Parts of Ethmoid bone formation superior and middle conchae.
Two Inferior nasal conchae are separate facial bone present lateral side of nose .
It functions is warm the air before goes to the lungs.it also humidity the air and filter the air ,trap dust and bacteria.
MANDIBLE ( LOWER JAW BONE )
This the lower jaw and only movable bone of the skull
In beginning in embryonic stage it starts as two bones and fuse at the midline .
The parts of Mandible are
1- Body
2-Ramus
3-Condylar process
4-Coronoid process
Articular surface for temperomendibular joint.
THYOID BONE
It is horseshoe -shaped bone or U shaped bone lying infront of the neck above the larynx and below the mandible.
This bone is only one bone which not connected with other bone .
It supports tongue and larynx
SINUSES –
Sinuses are air filed cavity present in frontal bone, sphenoid bone,maxillary bones .all these sinuses communicate with the nasal cavity.
These sinuses are lined with ciliated mucous membrane which propel mucus towards nose .
These sinuses are given clear voice and reduce the weight of the skull.
FONTANELLES OF THE SKULL
There are two fontanelles present in skull in baby .
1- Anterior fontanelle
2-Posterior fontanelle
1- ANTERIOR FONTANELLE
At birth bone formation is incomplete where three or more bone meets ( frontal bone and two parietal bones meets at anterior fontanelle so there is small gap which
is ossified or bone formation done until child is 12 to 18 months old.
-2-POSTERIOR FONTANELLE
Occipital bone and two parietal bones meets at this junction.here also bone formation is incomplete and small gap present which closes 2 to 3 months after birth.
This help in moulding of the baby’s head during child birth.
FUNCTION OF THE SKULL.
1- Cranium – protect the delicate brain tissue.
2- Bony eye sockets– provides protection to eye ball from injury and give attachment of the muscles of eye ball which helps in movement of the eye.
3-Temporal bone – Temporal bone protects all organs of ear .
4- Facial bone -sinuses of the face give resonance to the voice.
Face bone forms posterior part of nasal cavity.
5– Maxilla- maxilla form alveolar ridges in which the upper teeth are embedded..
6- Mandible -Mandible also form alveolar ridge in which the lower teeth embedded.
Mandible is the one only movable bone in the skull which function is chewing food.