1. Dental Anatomy & Nomenclature

having short crowns, well-developed short roots, and only narrow canals in the roots (short teeth)

brachydont

What animals have brachydont teeth?

D
C
P
H

• dogs

• cats

• primates

• humans

high crowns that erupt throughout life providing extra material for grinding food particulates down

hypsodont

What animals have hypsodont teeth?

H
C
O

• horses

• cows

• other herbivores

Animals have what categories of teeth?

incisors, canines, premolars, and molars

pronounced point on the occlusal or most coronal portion of a tooth

cusp

holds the tooth in

periodontal ligament

anything below the gingiva

root

Label this part of the tooth.

crown

Label this part of the tooth.

root

Label this part of the tooth.

cementum

Label this part of the tooth.

pulp

Label this part of the tooth.

cusp

Label this part of the tooth.

enamel

Label this part of the tooth.

dentin

Label this part of the tooth.

cementoenamel junction (neck)

Label this part of the tooth.

gingiva

Label this part of the tooth.

periodontal ligament

Label this part of the tooth.

alveolar bone

Label this part of the tooth.

apex

What covers the tooth crown?

enamel

What is the hardest substance in the body and is 96% mineral by weight (hydroxyapatite crystals)?

enamel

What is enamel formed by?

amebloblasts in root bud

When does amelogenesis stop?

prior to tooth eruption

When is the enamel incapable of repair?

after eruption (enamel you have after eruption is all you get)

What is normal enamel thickness in cats?

< 0.1 to 0.3 mm

What is normal enamel thickness in dogs?

< 0.1 mm to 0.6 mm

What is the purpose of the enamel?

effective barrier to heat/cold/sweet sensitivities and bacterial entrances into the tooth

What makes up the bulk of the tooth?

dentin

What percent of dentin is inorganic (mineral)? What percent is organic (water, collage, and mucopolysaccharides)?

70%; 30%

Dentin is comprised of _____ _____ that communicate between pulp and dentin, dentin/enamel, and dentin/cementum junctions.

dentinal tubules

What is significant about the dentinal tubules?

contain odontoblasts that produce dentin throughout the life of the tooth when the the tubule is exposed

What causes sensitivity within the dentin?

odontoblast processes that extend into the dental tubules along with fine nerve endings

What are the types of dentin?

primary, secondary, and tertiary (reparative) dentin

When enamel and dentin is gradually lost as the result of a local insult (mechanical wear), what do odontoblasts or odontoblast-like cells product? Why?

tertiary (reparative) dentin; to protect pulp

What is being shown here?

tertiary (reparative) dentin

hard tissue forming the surface of the root

cementum

What attaches to the cementum?

periodontal ligament and gingiva

________ produce cementum at the ________ of the ________.

cementoblasts; apex; root

For how long is cementum produced?

throughout life

What happens to cementum with age?

increases the width with age

What is the effect of chronic irritation on cementum?

can cause hypercementosis and lock the tooth into the alveolar socket

What is the effect of the loss of cementum?

prevents reattachment of the periodontal ligament

fibrous connective tissue which fills space between cementum of the tooth root and alveolar bone

periodontal ligament

What is the periodontal ligament composed of?

Sharpey’s fibers (collagen bundles in various shapes and orientations)

What are the functions of the periodontal ligament?

S
T
A
S
P

• shock absorption

• transmits occlusal forces

• attaches tooth to bone and cementum

• supplies nutrients

• provides tactile and proprioceptive information

What are you stretching when removing a tooth?

periodontal ligament

soft tissue connective tissue encased in root canal containing nerves, fibroblasts, collagen fibers, blood, and odontoblasts, which produce dentin throughout the life of the tooth

pulp

What happens to the pulp chamber/root canal as the animal ages?

it narrows

What fills in the pulp as the animal ages?

secondary dentin

Which tooth is from a young animal and which is from an old animal?

left = young tooth

right = old tooth

________ lining the pulp chamber and root canal produce ________ ________, causing the pulp to become ________ as the animal ages.

odontoblasts; secondary dentin; narrower

What is the purpose of the enamel bulge?

protects from things going into the gums

Label this part of the tooth.

crown (coronal)

Label this part of the tooth.

neck

Label this part of the tooth.

cementum

Label this part of the tooth.

root (apical)

Label this part of the tooth.

enamel

Label this part of the tooth.

dentin

Label this part of the tooth.

interradicular bone

Label this part of the tooth.

periodontal ligament space

Label this part of the tooth.

furcation

Label this part of the tooth.

pulp chamber

Label this part of the tooth.

root canal

Label this part of the tooth.

alveolar canal

What are the 4 components of the periodontum?

G
C
P
A

• gingiva

• cementum

• periodontal ligament

• alveolar bone

What is affected by and ultimately lost from periodontal disease?

the periodontium

normal, physiological space between the free gingiva and the tooth surface

gingival sulcus

What is the normal sulcus depth for dogs?

less than 3 mm

What is the normal sulcus depth for cats?

less than 1 mm

Where are you probing?

gingival sulcus

gingiva that is attached to the bone

attached gingiva

gingiva that goes on to the tooth

free gingival margin

Label this part of the gingiva.

alveolar mucosa

Label this part of the gingiva.

mucogingival junction

Label this part of the gingiva.

free gingival margin

Label this part of the gingiva.

attached gingiva

Label this part of the gingiva.

gingival sulcus

What directional term is this?

distal

What directional term is this?

mesial

What directional term is this?

lingual

What directional term is this?

labial

What directional term is this?

buccal

toward the apex of the root

apical

toward the tip of the crown

coronal

area or structure apical to the gingival margin

subgingival

area or structure coronal to the gingival margin

supragingival

mesial or distal surfaces of a tooth in close contact with an adjacent tooth

proximal

space between adjacent teeth

interproximal

surface of a tooth that faces the tooth of the opposing arcade

occlusal

refers to the surface of the tooth facing the vestibule or lips

vestibular (buccal and labial are acceptable alternatives)

surface of a mandibular tooth facing the tongue

lingual

surface of a maxillary tooth facing the palate

palatal

interproximal surface of a tooth that faces rostrally or towards midline of the dental arch

mesial

interproximal surface of a tooth that faces caudally or away from the midline of the dental arch

distal

refers to a structure closer to, or a direction toward the tip of the nares

rostral

refers to a structure closer to, or a direction toward the tail

caudal

What is the modified triadan tooth numbering system for permanent teeth in dogs and cats? What about deciduous teeth?

100s, 200s, 300s, 400s; 500s, 600s, 700s, 800s

What is the modified triadan tooth numbering system for the permanent upper right maxillary teeth?

100s

What is the modified triadan tooth numbering system for the permanent upper left maxillary teeth?

200s