Week 6 Facial Bone Nasal Bone Anatomy Facial

Week 6 Facial Bone, Nasal Bone Anatomy, Facial Bone, Nasal Bone Projections 1

FACIAL BONES 14 bones in the face, not including the hyoid bone 6 paired bones 2 unpaired bones 2

Nasal 13 bone 2 1 3 4 11 10 9 88 6 7 5 3

Nasal Bones Two small, thin bones Vary in size and shape in individuals Form superior bony wall of nasal cavity Ø Commonly called “bridge of nose” Articulations Ø Ø With each other in midsagittal plane Superior = frontal bone Posterosuperior = perpendicular plate of ethmoid bone On each lateral side = maxillae 4

Lacrimal Bones The two smallest bones in the skull Located in anterior part of medial wall of orbits between labyrinth of ethmoid and maxilla Each bone contains a lacrimal foramen through which the tear duct passes Articulations Ø Ø Frontal Ethmoid Maxilla Inferior nasal concha 5

Maxillary Bones Largest immoveable bones of face Each articulates with all other facial bones, except for mandible Also articulate with frontal and ethmoid cranial bones Form part of lateral walls and most of floor of nasal cavity Form part of floor of orbit 6

Maxillary Bones Form three fourths of roof of mouth Have zygomatic process that articulate with zygoma to form part of cheek Body contains large, pyramidal cavity = maxillary sinus Infraorbital foramen = located under each orbit for passage of infraorbital nerve and artery 7

Maxillary Bones Alveolar process = inferior borders of spongy bone that support roots of teeth Anterior nasal spine = forward, pointed process at their midline junction Acanthion = midpoint of this junction 8

Maxillary Bone 9

Palatine Bones Two L-shaped bones composed of vertical and horizontal plates Horizontal plates articulate with maxillae to complete the posterior fourth of bony palate (roof of mouth) Vertical portions extend upward between maxillae and pterygoid processes of sphenoid in posterior nasal cavity Superior tips of vertical plates assist in forming posteromedial orbit 10

Palantine Bones 11

Hard Palate 12

Inferior Nasal Conchae Extend diagonally and inferiorly from lateral walls of nasal cavity at its lower third Long, narrow, very thin bones with a lateral curl Ø Gives scroll-like appearance Upper two nasal conchae are processes of ethmoid bone 13

Inferior Nasal Concha 14

Zygomatic Bones Articulations Superior = frontal bone Lateral = zygomatic process of temporal bone Anterior = maxilla Posterior = sphenoid 15

Zygomatic Bones 16

Vomer Thin plate of bone situated in MSP of floor of nasal cavity Forms inferior nasal septum Superior border articulates with body of sphenoid bone Superior part of anterior border articulates with perpendicular plate of ethmoid bone Posterior border is free 17

Vomer 18

Mandible Largest and densest bone of the face Body = curved horizontal portion Rami = two vertical portions on each side of body Angle of mandible = junction of body and ramus Also called gonion Mental protuberance = anterior, triangular prominence 19

Mandible Symphysis = most anterior and central part where left and right halves of mandible fuse Alveolar process = superior border of body; consists of spongy bone that supports roots of teeth Mental foramina = small openings on each side below the second premolar; transmit nerves and blood vessels 20

Mandible Coronoid process = anterior process on top of ramus Condylar process = posterior process on top of ramus; articulates with mandibular fossa of temporal bone to form temporomandibular joint (TMJ) Mandibular notch = concave area at top of ramus between coronoid and condylar processes 21

Anatomy: Mandible Anterior and lateral aspects of mandible 22

Hyoid Bone Small U-shaped bone situated at the base of the tongue Accessory bone of axial skeleton – not a facial or cranial bone Only bone in the body that does not articulate with another bone 23

Anatomy: Facial Bones Lateral aspect of facial bones 24

Clicker Question Which facial bones form part of the hard palate? A. Palatine B. Mandible C. Zygoma D. Lacrimal 25

Clicker Question All of the following are part of the bony orbit, except: A. Palatine B. Zygoma C. Lacrimal D. Vomer 26

Essential Projections: Facial Bones Lateral Parietoacanthial (Waters method) Acanthioparietal (reverse Waters method) Posteroanterior (PA) axial (Caldwell method) 27

Lateral Facial Bones Patient position Ø Semi-prone or seated in upright anterior oblique Part position Ø MSP of head parallel with image receptor (IR) Ø Interpupillary line (IPL) perpendicular to IR Ø Infraorbitomeatal line (IOML) perpendicular to front edge of IR 28

Lateral Facial Bones Central ray (CR) Perpendicular to IR center Enters patient on lateral surface of zygomatic bone halfway between outer canthus and external acoustic meatus (EAM) Collimated field 8 x 10 inches (18 x 24 cm) 29

Lateral facial bones 30

Lateral facial bones 31

Lateral facial bones 32

PA Axial (Caldwell) Patient position Seated erect or prone MSP centered to midline Forehead and nose resting on table or upright Bucky Part position OML perpendicular to IR plane MSP perpendicular to IR centered to nasion 33

PA Axial (Caldwell) CR Ø Angled 15 degrees caudad Ø Exits nasion Ø For orbital rims, angle 30 degrees caudad (“exaggerated” Caldwell) Collimated field Ø 10 x 12 inches (24 x 30 cm) 34

PA Axial (Caldwell) 35

PA Axial(Caldwell) 36

PA Axial (Caldwell) 37

Parietoacanthial (Waters) Facial Bones Patient position Prone or seated upright Center MSP to midline of upright Bucky 38

Parietoacanthial (Waters) Facial Bones Part position Rest head on tip of extended chin Place orbitomeatal line (OML) to form 37 -degree angle with plane of IR Mentomeatal line (MML) perpendicular to IR MSP perpendicular to IR Center IR to level of acanthion 39

Parietoacanthial (Waters) Facial Bones CR Perpendicular to exit acanthion Collimated field 8 x 10 inches (18 x 24 cm) 40

Parietoacanthial (Waters) Facial Bones 41

Parietoacanthial (Waters) Facial Bones 42

Parietoacanthial (Waters) Facial Bones 43

Parietoacanthial (Waters) Facial Bones 44

Parietoacanthial (Waters) Facial Bones 45

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Parietoacanthial (Waters) Facial Bones Modifications for the Water’s projection: Ø Ø done to see entire orbital rims OML at a 55° angle to IR (use the LML for positioning) petrous ridges just below IOM 47

Parietoacanthial (Waters) Facial Bones-Modified 48

Parietoacanthial (Waters) Facial Bones Modifications for the Water’s projection: 49

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Acanthioparietal (Reverse Waters) Facial Bones 52

Acanthioparietal (Reverse Waters) Facial Bones CR Perpendicular to enter acanthion Center IR and CR Collimated field 10 x 12 inches (24 x 30 cm) 53

Acanthioparietal (Reverse Waters) Facial Bones 54

Acanthioparietal (Reverse Waters) Facial Bones 55

Acanthioparietal (Reverse Waters) Facial Bones 56

Acanthioparietal (Reverse Waters) Facial Bones 57

Acanthioparietal (Reverse Waters) Facial Bones 58

Essential Projections: Nasal Bones Lateral Water’s Caldwell 59

Lateral Nasal Bones Patient position Semiprone MSP of head horizontal Part position MSP parallel with tabletop IPL perpendicular to tabletop IOML is parallel with transverse axis of IR 60

Lateral Nasal Bones CR Ø Perpendicular to bridge of nose Ø Enters at a point ½ inch (1. 3 cm) distal to nasion Collimated field Ø 3 x 3 inches (8 x 8 cm) Ø Field should extend from the glabella to the acanthion and ½ inch beyond the tip of the nose 61

Lateral Nasal Bones 62

Lateral Nasal Bones 63

Lateral Nasal Bones 64

Lateral Nasal Bones 65

Pathologic Indications for Facial Radiography Fractures Blowout Tripod Le. Fort Coutrecoup Foreign Body Neoplasms Secondary Osteomyelitis TMJ Syndrome Osteomyelitis 66