FACE
The skeleton of the face is formed by 13 bones such as
2.zygomatic (cheek)bones
1 maxilla(originated as 2)
2 nasal bones
2 lacrimal bones
1 vomer
2 palatine bones
2 inferior conchae
1 mandible
Zygomatic (cheek) bones form the prominences of the cheeks
and part of the floor and lateral walls of the orbital cavities.
This originates as two bones,but fusion takes place before
birth.
The maxilla forms the upper jaw, the anterior part of the
roof of the mouth,the lateral walls of the nasal cavity and part of the floor
of the orbital cavities.
The alveolar ridge,or process, projects downwards and
carries the upper teeth.
On each is a large air sinus,the maxillary sinus,lined with
ciliated mucous membrane and with openings into the nasal cavity.
These are two small flat bones that form the greater part of
the lateral and superior surfaces of the bridge of the nose.
These two small bones are posterior and lateral to the nasal
bones and form part of the medial walls of the orbital cavities.
Each is pierced by a foramen for the passage of the
nasolacrimal duct that carries the tears from
the medial canthus of the eye to the nasal cavity.
The vomer is thin flat bone that extends upwards from the
middle of the hard palate to form most of the interior part of the nasal septum.
Superiorly it articulates with the perpendicular plate of
the etmoid bone.
These are two small L-shaped bones.
The horizontal parts unite to form the posterior part of the
hard palate and the perpendicular parts project upwards to form part of the
lateral walls of the nasal cavity.
At their upper extrimities they form part of the orbital
cavities.
Each concha is a scroll-shaped bone, which forms part of the
lateral wall of the nasal cavity and projects into it below the middle concha.
The superior and middle conchae are parts of the ethmoid
bone.
The conchae collectively increase the surface area in the
nasal cavity,allowing inspired air to be warmed and humidified more
effectively.
This is the lower jaw , the only movable bone of the skull.
It originates as two parts that unite at the midline.
Each half consists of two main parts: a curved body with the
alveolar ridge containing the lower teeth
and a ramus,which projects upwards almost at right angles to the posterior end
of the body.
At the upper end the ramus divides into the condylar process
which articulates with the temporal bone to form the tempomandibular joint and
the coronoid process, which gives attachement to muscles and ligaments that
close the jaw.
The point where the ramus joins the body is the angle of the
jaw.
This is an isolated horseshoe-shaped bone lying in the soft
tissues of the neck just above the larynx and below the mandible.
It does not articulate with any other bone,but is attached
to the styloid process of the temporal bone by ligaments.
It supports the larynx and gives attachment to the base of
the tongue.
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