Radiographic Anatomy of the Skull Dr. Meghan Woodland November 25, 2010.
Patient Preparation: Radiographs should be taken under general anaesthesia In critical cases, lateral and VD views can be obtained with minimal sedation Standard skull series: Lateral VD Nasal, Bulla and Dental series: various oblique and open-mouth views.
Typical Radiographic View 1. Open mouth VD Direction of X-rays
This view is used to evaluate the nasal cavity, which is important in animals with nasal discharge. Joe P. Morgan
Note the increased opacity in the left nasal passage
Typical Radiographic View 2. Lateral View
Can be used to evaluate for nasal or frontal bone fractures in trauma patients Joe P. Morgan
Radiograph is oblique as the dog was awake and difficult to keep still.
Typical Radiographic View 3. Frontal Sinus View Direction of X-rays X-ray film
Important for evaluating for the presence of sinusitis in patients with nasal discharge. Joe P. Morgan
Note the increased opacity within the left frontal sinus
Normal Appearance DV/VD
Frontal Bone & Sinus
Zygomatic Arch
Maxillary Bone
Mandible
Tympanic Bullae
Horizontal Ear Canal
Note the decreased amount of air within the right ear canal.
Note the mineralization of both ear canals
Temporomandibular Joint
Normal Appearance Lateral
Mandible
Mandibular symphyseal fracture
Maxillary Bone
Zygomatic Bone
Orbital Margin
Normal cat bulla on lateral or oblique view
Coronoid Process of the Mandible
Temporomandibular Joint
Condylar Process of Mandible
Retroarticular Process
Angular Process of the Mandible
Close up of Skull TMJ Joint Condylar Process Retroarticular Process Angular Process
Normal Appearance Open Mouth VD
Ethmoid Turbinates
Maxillary Turbinates
Turbinates Turbinate pattern changes at the level of PM3. Maxillary turbinates have a linear pattern Ethmoid turbinates have a more coarse pattern
Vomer Bone Nasal Septum Vomer bone
Palatine Fissure
Open Mouth VD and CT Compare 1. Radiograph on the left 2. CT images on the right Note the turbinate patterns at the different levels
Normal Appearance Frontal Sinus View
Normal Appearance Lateral View
Frontal Sinus
Ethmoid Turbinates
Nasal Turbinates
Nasopharynx
Maxillary Recess
Tooth Root Abscess
Normal Dental Formula (Canine) Maxillary teeth 3 (x2) Incisors 1 (x2) Canine 4 (x2) Premolars 2 (x2) Molars
Normal Dental Formula (Canine) Mandibular teeth 3 (x2) Incisors 1 (x2) Canine 4 (x2) Premolars 3 (x2) Molars
Normal Dental Formula (Feline) Maxillary teeth 3 (x2) Incisors 1 (x2) Canine 3 (x2) Premolars 1 (x2) Molars
Normal Dental Formula (Feline) Mandibular teeth 3 (x2) incisors 1 (x2) canine 2 (x2) Premolars 1 (x2) Molars
Deciduous Teeth Time of Replacement Incisors 3-5 months Canines 5-7 months Premolars 5-6 months
Deciduous Teeth
Deciduous Teeth Deciduous teeth Permanent teeth Permanent teeth
Normal Teeth: Age Related Changes As an animal ages the teeth will: have a decreased pulp cavity closure of the apical foramen regression of alveolar crest sclerosis of alveolar bone
Age Related Changes As an animal ages the teeth will: have a decreased pulp cavity closure of the apical foramen regression of alveolar crest sclerosis of alveolar bone
Age Related Changes As an animal ages the teeth will: have a decreased pulp cavity closure of the apical foramen regression of alveolar crest sclerosis of alveolar bone
Age Related Changes As an animal ages the teeth will: have a decreased pulp cavity closure of the apical foramen regression of alveolar crest sclerosis of alveolar bone
Age Related Changes Increasing Age
Age Related Changes Note the decreased size of pulp cavity
Normal Tooth Structure
Normal Tooth Structure Crown - covered with enamel and above gum line
Normal Tooth Structure Root - below gum line surrounded by bone
Normal Tooth Structure Pulp Cavity - contain blood vessels and nerves radiolucent zone in center to tooth
Normal Tooth Structure Periodontal Membrane - radiolucent (black) line surrounding the tooth root
Normal Tooth Structure Lamina dura - sclerotic (white) line just outside the periodontal ligament
The End