Radi 106 Facial Bones, Nasal Bones, Optic Foramen, Zygomatic Arches

How many facial bones are there

14

How many cranial bones are there

8

Maxillary Bones

Largest immovable facial bones; articulate with 2 cranial bones and seven facial bones

Maxilla assists in the formation of three cavities of the face

Mouth, nasal cavity, one orbit

Each maxilla consists of

• centrally located body

• Frontal process

• Zygomatic process

• Alveolar process

• Palatine process

• Anterior nasal spine

Zygomatic Bones

Lateral to the zygomatic process of each maxilla and makes up the cheek and lower outer portion of the orbit; articulated with 3 cranial bones and with one facial bone

Zygomatic arch

Formed by the posterior portion of the zygomatic bone and the zygomatic process of the temporal bone

Zygomatic prominence

Positioning landmark, refers to the prominent portion of the zygomatic bone

What two bones make up the zygomatic arch

Zygomatic bone and temporal bone

Nasal and lacrimal bones

Thinnest and most fragile bones in the entire body

Anteriorly on the medial aide of each orbit

Associated with the tear ducts

Nasal bones

Two fused bones that form the bridge of the nose

Anterior and superior to the frontal process of the maxilla

Articulate with 2 cranial bones and 2 facial bones

What is the nasion

Two nasal bones and the frontal bone join

Lacrimal bones articulate with

2 cranial bones and 2 facial bones

Nasal Conchae

Two thin, curved bones located within the nasal cavity

Superior and middle nasal conchae are shaped similarly but are a part of the

Ethmoid bone

Three conchae divide the nasal cavities into compartments which

Clean and warm the air before it reaches the lungs

Inferior nasal conchae articulates with

1 cranial bone and 3 facial bones

Palatine bones

• L-shaped

• Horizontal portion and vertical portion

• Horizontal portion helps form the posterior portion of the hard palate

• Articulate with 2 cranial bones and 4 facial bones

Vomer

• thin, triangular shaped bone

• With the ethmoid bone, forms the nasal septum

• Marked by small furrow-like depressions for blood vessels

• Articulates with 2 cranial bones and four facial bones and septal cartilage

Mandible

Largest facial bone and is the only movable bone in the adult skull

• starts out as two bones but joins together

What age does the mandible join together

1

Features of the mandible

• angle

• Body

• Ramus

• Alveolar process

• Symphysis

Mentum

Area below the symphysis projecting forward as the chin

Mental point

Center of the mentum

Mental foramina

Passage ways for nerves and blood vessels

Mandibular notch

U-shaped notch at the end of each ramus

Coronoid process

Process at the anterior end of the notch

Condyloid process

Posterior process of the notch, has a head and a neck

Temporomandibular joint

Head of the condyloid process fits into the temporomandibular fossa of the temporal bone to form this joint

What two parts make up the TMJ joint

Condyloid process and fossa of temporal bone

Orbits

Coned shaped, bony wall structure

rim of the orbit is called

The base

Posterior portion of the orbit is the

Apex

Each orbit is composed of what bones

• frontal bone

• Maxilla

• Zygoma

• Lacrimal

• Sphenoid

• Ethmoid

• Palatine

Each orbit is contains three openings which provide passage for specific cranial nerves

• optic foramen

• Superior orbital fissure

• Inferior orbital fissure

Sphenoid strut

Small root of bone separating the superior orbital fissure and optic canal

TMJ is what type of joint

Synovial (diarthrodial)

Synovial (diarthrodial) is a

Freely movable joint

Sutures, teeth, mandible and maxillae are what type of joint

Fibrous (synarthrodial)

Fibrous (Synarthrodial) is an

Immovable joint

Tripod

Blow to the cheek resulting in the zygoma to be fractured in 3 places

Leforte

Severe bilateral horizontal fractures of the maxillae

Contre-coup

Injury/fracture to one side caused by an impact to the opposite side

In the parietoacanthial projection (waters method) where are the Petrous ridges projected

below (inferior) to the maxillary sinuses

In the parietoacanthial projection (modified waters method) where are the petrous ridges projected

lower half of the maxillary sinuses

In the PA Axial Projection (Caldwell method) where are the petrous ridges projected

Lower one-third of the orbits

In the parieto-orbital oblique projection (Rhese method) where is the optic foramen projected

Lower outer quadrant of the orbit