Headwork Part 2: Facial & Nasal Bones

1?

Zygoma

2?

Vomer 

3?

Maxilla

4?

Mandible 

5?

Inferior nasal concha

6?

Lacrimal bone

Nasion 

A?

Frontal bone

B?

Zygomatic bone

C? 

Alveolar 

D?

Acanthion

E?

Anterior nasal spine

1? 

Maxillary sinuses

2?

Alveolar process

3?

Zygomatic process

4? 

Frontal process

Zygomatic Arch

Formed by zygomatric bone and temporal bone

Zygomatic arch

Zygomatic prominence

1?

Palatine process

2? 

Pterygoid hamulus 

3?

Palatine bones

What is the green?

Superior nasal concha

1? 

Septal cartilage 

2?

Perpendicular plate

3?

Vomer

How many facial bones are there? 

14

Facial Bones

Maxillae (2), zygoma (2), lacrimal (2), nasal (2), inferior nasal conchae (2), palatine (2), vomer (1), mandible (1)

1?

Nasal bone

2?

Lacrimal

3?

Maxilla

4?

Mandible

5?

Zygoma

6?

Vomer

7?

Inferior nasal concha

1?

Glabella 

2?

Interpupillary line

3?

Inner canthus

4? 

Acanthion 

5? 

Mental point

6?

Gonion

Facial bone joint classification

Fibrous, synarthrodial (immovable)

Mandible joint classification 

Synovial, hinge and gliding 

A?

Anterior nasal spine

B?

Zygomatic arch

D? 

Mastoid process 

E?

Gonion

F?

Foramen magnum

G?

Zygomatic prominence

H?

Maxillary sinus

I? 

Bony nasal septum 

Orbit Composition

Ethmoid bone, frontal bone, sphenoid bone, lacrimal bone, maxilla, palatine, zygoma

A?

Frontal bone

B? 

Ethmoid bone

C?

Sphenoid bone

1?

Lacrimal

2?

Palatine

3?

Maxilla

4?

Zygoma

1? 

Optic foramen 

2?

Sphenoid strut

3?

Superior orbital fissure

4? 

Inferior orbital fissure 

What is the superior angle of the orbits?

30°

What is the medial angle of the orbits?

37°

What is the wide, round anterior half of the orbits called?

Base

What is the long, narrow posterior part of the orbits called? 

Apex 

Blowout Fracture

Result of a forceful blow to the orbit (ex. fist or baseball); causing one or more of the orbital walls to fracture, but the orbital rim stays intact

What “sign” on a CT shows a blowout fracture?

Tear drop

Blowout fracture

Tripod Fracture (ZMC Fracture) 

Comprise fractures of the zygomatic arch, inferior orbital rim/anterior and posterior maxillary sinus walls, lateral orbital rim

What does ZMC fracture stand for?

Zygomaticomaxillary complex

Tripod fracture (ZMC Fracture) 

Le Fort Fracture

Bilateral horizontal fracture of the maxillae that causes instability; 3 levels

Le Fort I

Separation of the hard palate from the upper maxilla due to a transverse fracture running through the maxilla and pterygoid plates at a level just above the floor of the nose

Le Fort II 

Fractures transect the nasal bones, medial-anterior orbital walls, orbital floor, inferior orbital rims and finally transversely fracture the posterior maxilla and pterygoid plates

Le Fort III

Highest level Le Fort fracture; results in craniofacial disjunction (essentially separates the maxilla from the skull base)

Le Fort I

Le Fort II

Le Fort III

Zygomatic Arch Fracture

A fracture of the zygomatic arch; may be simple or comminuted

Zygomatic arch fracture

Metal foreign body

Nasal Bone Fracture

Fracture to the nasal bone; often a transverse fracture

Nasal bone fracture 

Parietoacanthial waters collimation 

10×12 

Left lateral collimation

8×10

PA Axial Exaggerated Caldwell collimation

9×6

SMV collimation 

12×10

Facial Bones Routine

• Parietoacanthial waters

• Left lateral 

• PA axial exaggerated caldwell 

• SMV

Nasal Bones Routine

• Parietoacanthial waters

• Right and left laterals

Parietoacanthial waters (nasal bone) collimation

6×6

Right and left lateral (nasal bone) collimation 

4×4 

Parietoacanthial Waters

• Neck hyperextended

• OML 37° with IR

• MML & MSP perpendicular to IR

• CR exiting acanthion

Left Lateral

• Anterior oblique

• MSP parallel to IR

• IPL & IOML perpendicular to IR

• CR at point halfway between outer canthus and EAM

Right and Left Lateral (nasal bone) 

• Anterior oblique

• MSP parallel to IR

• IPL & IOML perpendicular to IR

• CR at point ½ distal to the nasion 

PA Axial Exaggerated Caldwell

• Forehead and nose against IR

• OML perpendicular to IR

• 30° caudad tube angle

• CR exits the infra-orbital rim

SMV

• Hyperextend neck

• IOML nearly parallel with IR

• Head rested on vertex - MSP perpendicular

• CR perpendicular to IOML through gonion, ¾ in superior to EAM

Parietoacanthial Waters Evaluation 

• Distance between the lateral border of the skull and the orbits should be equal on both sides

• Petrous ridges should be projected immediately below the maxillary sinuses

Left Lateral Evaluation

• Zygomatic bone centered

• Superimposed mandibular rami

• Superimposed orbital roofs

• Sella turcica in profile