Equine dentistry

Question 1

Normal anatomy

Answer 1

incisors
canines
wolf teeth (vestigial 1st premolar)
cheek teeth

Question 2

equine adaptions

Answer 2

interdental space
limited rostrocaudal movement of temporomandibular space (TMJ)
increased lateral movement of TMJ
TMJ allows occlusal contact of all cheek teeth simultaneously
well developed masticatory musculature
adapted for constant grinding - hypsodont, irregular enamel edges

Question 3

mastication

Answer 3

opening, closing, power strokes

tongue moves food around mouth

Question 4

Triadan system of dental nomenclature*

Answer 4

1/2/3/401-11 from right to left, top to bottom

Question 5

ages of eruption of equine teeth*

Answer 5

see table in notes

molars later than incisors

Question 6

development of cheek tooth

Answer 6

maxillary wider than mandibular arcade

occlusal surface at 10-15 degrees

Question 7

normal cheek teeth anatomy*

Answer 7

cementum - attaches to periodontal ligament
dentine - bulk of tooth, tubular structure
enamel - hardest tissue, laminated sheets
pulp - blood + nerve supply to tooth
infundibulum - infolding of enamel from occlusal surface

Question 8

dental exam

Answer 8

distant observation
external exam - condition score
head exam - symmetry, LNs, discharge, pain
oral exam - incisors malocclusion, interdental space, cheek teeth

Question 9

oral exam

Answer 9

restraint
head support
illumination

Question 10

additional diagnostic aids

Answer 10

mirror
probes/picks
oral endoscopy
radiography
scintigraphy

Question 11

effect of enamel overgrowth

Answer 11

prevent jaws from moving freely
cause pain, quidding + weight loss
biting problems
headshaking
shear mouth

Question 12

Shear mouth

Answer 12

occur over long time

mouth may remodel to compensate

Question 13

Shear mouth - treatment

Answer 13

reduce buccal and lingual points
reduce angle
regular treatments every 3-6 months
address any underlying pathology

Question 14

rasping blades

Answer 14

carbide chip - cheap

solid tungsten carbide blades - better

Question 15

routine rasping - 4 types

Answer 15

straight head, long length
obtuse angled head, long length
angled offset head, medium length
5 float

Question 16

power tools

Answer 16

remove hooks quickly

care palatine artery

Question 17

Retained deciduous premolars (‘caps’)

Answer 17

shed at 2.5, 3 + 4 years

if retained - anorexia, poor performance, malocclusion

Question 18

rostral + caudal overgrowths

Answer 18

106, 206, 311, 411

usually with rostral displacement of maxillary arcade

Question 19

focal overgrowth - causes

Answer 19

diastema
displaced teeth
lost teeth
fractured teeth

Question 20

removal of overgrowths

Answer 20

care - pulp exposure, heat production

overgrowth have less occlusal contact, less secondary dentine, therefore increased risk of pulp exposure

Question 21

pulp exposure

Answer 21

identify by probing 2ndary dentine overlying pulp horns
can be a cause + consequence of apical tooth infections
can be from over rasping

Question 22

infundibular caries

Answer 22

can lead to septic pulpitis
80% of horses > 15 yrs old are affected
usually benign
can cause sagittal fracture of the tooth

Question 23

peridontal disease

Answer 23

primary is rare - caused by diastemata
v.painful
increased incidence with age
begins with gingivitis with a pocket formation - debris get stuck and bacteria build up

Question 24

diastemata

Answer 24

often normal in aged horses

food trapped between teeth + compacted

Question 25

diastemata - treatment

Answer 25

monitor, widen, extraction

more short foods

Question 26

removal of impacted food

Answer 26

long handled dental
high pressure water or air picks
transient improvement only

Question 27

displaced cheek teeth - developmental

Answer 27

overcrowded arcades during eruption

often bilateral

Question 28

displaced cheek teeth - acquired

Answer 28

more common

usually lower 10s and 11s

Question 29

cheek teeth fractures

Answer 29

can be secondary to severe infundibulur caries
can lead to septic pulpitis
can cause acquired overgrowths

Question 30

mandibular apical tooth infections

Answer 30

most common in young horses
asymmetrical jaw swelling
oral involvement
diagnosis easy with radiography

Question 31

Maxillary apical tooth infections - aetiology

Answer 31

infundibular caries
pulp exposure - premature or after fracture
periodontal fistulation

Question 32

oral endoscopy

Answer 32

close up of back of mouth
rigid or fibre optic scope
expensive

Question 33

dental radiography

Answer 33

low sensitivity, high specificity

Question 34

gamma scintigraphy

Answer 34

shows mineralised and non-mineralised tissue
sensitive but only mild specificity
non invasive
images whole head simultaneously

Question 35

computed tomography (CT)

Answer 35

rotating x-ray tube

advantages - windowing

Question 36

radiographic signs - apical tooth root infections

Answer 36

periapical sclerosis

periapical halo

Question 37

apical tooth infections - treatment

Answer 37

antibiotics
currettage (surgical instrument)
tooth removal

Question 38

oral extraction procedure

Answer 38

sedation
local blocks
separation
placement
grip
patience

Question 39

wolf teeth

Answer 39

no deciduous precursors
erupt at 1 year of age
many lost
can be displaced

Question 40

wolf teeth - extraction

Answer 40

can involve extensive elevation of tooth
can cause injury if inexperienced
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