Unit 2: Oral Anatomy (Cram)

Most common headshape

Mesaticephalic

Short and wide headshape. These breeds have crowded, rotated premolar teeth

Brachycephalic

Long and narrow head shape

Dolichocephalic

Which cat breed in known for being brachycephalic?

Persian

Which cat breed is known for being dolichocephalic?

Siamese

What kind of bite does this mesaticephalic dog have?

Scissor bite

What kind of bite does this brachycephalic dog have?

Undershot bite

What kind of bite does this dolichocephalic dog have?

Overshot bite

What kind of bite does this brachycephalic dog have?

Upper jaw, made of many bones

Maxilla

Lower jaw

Mandible

The division between the two mandibles

Mandibular symphysis

The portion of the mouth that consists of hard bone covered by mucous membranes

Hard palate

The posterior portion of the roof of the mouth extending down the throat. Does not have bone under it

Soft palate

Irregular ridges on the mucous membrane of the hard palate

Rugae

The space between the cheek/lips and teeth

Vestibule

The area where the two jaws join at the back of the oral cavity

Fauca

Epithelial tissue that is harder and more tightly attached to supportive tissue in the oral cavity

Gingiva

The space between the tooth and surrounding structures other than the tissues in the oral cavity (hint: we measure this with a probe)

Sulcus

The mucous membranes that lines the inside of the mouth

Oral mucosa

Where the upper and lower lips meet (at the corners of the mouth)

Commisure

Where the gingiva meets the mucous membranes. There is a line across the gums

Mucogingival line

Where the mucous membranes transition to skin

Mucocutaneous junction

Refers to the way the teeth fit together

Occlusion

Space or gap between two teeth

Diastema

Tooth surface that faces the lips, only the incisor teeth

Labial

Tooth surface that faces the hard palate, only top teeth

Palatal

Tooth surface that faces the tongue, only bottom teeth

Lingual

Premolar and molar tooth surface that faces the lips (cheeks)

Buccal

Tooth surface at the back of the tooth

Distal

Tooth surface at the front of the tooth

Mesial

Tooth surface in the space between each tooth

Interproximal surface

The very top of the tooth (crown surface)

Note: May be asked "what tooth surface faces the lips"? If the question is not specific about incisors or premolars/molars, the answer is occlusal

Occlusal

Directional term meaning towards the crown of the tooth

Coronal

Directional term meaning towards the apex of the tooth

Apical

Label A–J on this diagram
A – Alveolar bone
B – Cementum
C – Sulcus
D – Enamel
E – Dentin
F – Crown
G – Pulp cavity
H – Root
I – Periodontal ligament
J – Apical delta

What are the red and black arrows pointing to on the tooth?

Red – Furcation
Black – Apex

Fill in the blank: ______ is the hardest tissue in the body, it is made mostly of mineral crystals, mainly ______.

Enamel, calcium

If enamel is so hard, why wouldn't you want a tooth completely comprised of it?

It is hard but also brittle, an 100% enamel tooth would fracture easily

Cell that forms enamel

Remember: Blast for Build

Ameloblasts

What is this condition of minimal calcification of the enamel?

Enamel hypoplasia

True or false: Dogs and cats have thicker enamel compared to humans. This is why dogs can chew on bones and sticks without enamel damage

False. Dogs and cats have a thinner enamel than humans. Chewing on rocks, sticks, and bones, can easily wear away a dog's enamel, causing permenant damage

Substance that makes up the majority of the tooth structure. It forms the layer just below the enamel of the crown and the cementum of the root

Note: Dentin is also hard, as hard as bone, but not as hard as enamel

Dentin

Cells that make dentin throughout the life of the tooth

Note: Dentin has a regenerative capacity

Odontoblasts

Cells that breakdown dentin and other tooth substances

Note: Hence why lesions involving these cells are called odontoclastic resorptive lesions

Odontoclasts

Substance that covers the outermost surface of the tooth roots. Similar to bone and is the only substance that periodontal ligaments and gingiva will form attachments to

Note: If cementum is damaged deep pockets around the tooth will result

Cementum

True or false: Enamel lacks nerve endings, while dentin and cementum have nerve endings, this is why they are painful when exposed

True

Fill in the blank: Dentin is arranged in _______ which radiate outwards from the _______ chamber towards the enamel

Dentin is arranged in tubules which radiate outwards from the pulp chamber towards the enamel
Note: These tubules are easily colonized by bacteria if dentin is exposed

Type of dentin that is created BEFORE the tooth erupts

Primary (1°) dentin

Type of dentin that is created continuously AFTER the tooth erupts

Secondary (2°) dentin

True or false: The creation of secondary dentin causes an animal's teeth to grow bigger over their lifetime

False. Dentin grows inwards rather than outwards. It makes the pulp chamber smaller as the animal ages

Type of dentin that is produced in areas exposed to injury. It is darker and more irregular than primary or secondary dentin

Tertiary (3°) dentin

The exposure of which tooth structure causes sensitive teeth: enamel, dentin, or pulp?

Dentin

Cells that produce cementum at the root apex throughout the life of the tooth

Cementoblasts

Hardened, keratinized epithelial tissue. Like a callused mucous membrane

Gingiva