Small mammal dental disease

what do grases contain lots of that aid hypsodontal animals?

• silica phytoliths

what is a very important behaviour for hypsodont?

• gnawing

what kinds of animals are elodonts?

• guinea pigs

• chinchillas

• degus

• rabbits

what does elodont mean?

• continuously growing teeth

• large occlusal surface for grinding

• herbivorous diet

what animals are anelodonts?

• rats

• mice

• hamsters

• gerbils

• squirrels

what does anelodont mean?

• short crowned

• rooted cheek teeth

• don’t grow

tend to be grain eaters, omnivores

out of elodonts and anelodonts which animals tend to present with more dental disease?

• elodonts

which teeth are most commonly affected in

1. elodonts

2. anelodonts

1. cheek teeth mostly, incisors too

2. incisor teeth

what is the rabbit dental formula?

upper - 2, 0, 3, 3

lower - 1, 0, 2, 3

which teeth are missing in the modified triadan system in rabbits:

1. upper

2. lower

1. 103, 203, 104, 204, 105, 205

2. 302/3, 402/3, 304, 404, 305, 405

what are adaptions of the chisel shaped teeth in rabbits?

• these are the incisor teeth

• they have uneven wear

• a sharp cutting edge

where do we find enamel on rabbit incisors?

• more on the labial side

• softer dentine on the lingual aspect

how do rabbits keep their teeth in shape?

• eating

• gnawing

• occasional grinding

what does the enamel fold create in rabbits?

• interlocking of teeth

• creates a grinding surface

what does ‘cheek teeth’ refer to?

• molars and premolars as one functioning unit

what are peg teeth?

• 2 extra incisors in rabbits that are found behind their upper incisors

• these rest the against lower incisors as the mouth shuts (aka rabbits have an underbite)

• this aids with occlusion and wear

do rabbit cheek teeth touch at rest? why?

• no because the mandibular arcade = narrower than maxillary

what edges of which teeth occlude in rabbits?

• lingual edge of maxillary teeth

• with the buccal edge of mandibular teeth

in rabbits do we distinguish between the crown and root?

• no, the entire tooth is known as the crown

• the tooth within the jaw = reserved crown

what is the shape of the surface of rabbit teeth?

• not horizontal - they have natural curvature

what are some consequences of continuously growing teeth?

• high calcium is required

• we can see rapid changes very quickly

• dental disease exists often as a secondary disease, as well as first

what is important to note about rabbit nasolacrimal ducts?

• they’re in very close association with the teeth

• therefore likely will see blockage, inflammation and infection - especially fi we have underlying teeth problem

what are rat and mice dental formulae:

1. upper

2. lower

1. 1,0,0,3

2. 1,0,0,3

what is guinea pig, chinchilla and degu dental formula?

1. upper

2. lower

1. 1,0,1,3

2. 1,0,1,3

in non rabbit rodents, outline the incisors:

1. open/closed root?

2. pigmentation?

3. where dow e find enamel

1. open

2. yes, a superficial layer of enamel

3. on the cranial aspect

what causes tongue entrapment in guinea pigs

• maxillary cheek teeth angled outwards, mandibular inwardly

what is a leading problem for rabbit and rodent pet dental disease?

• DIET

what can go wrong in the diet that can cause dental issues?

1. not enough vegetation

2. selective eating

3. sugary treats and fruit

4. deficiencies in vitamin C, D and selenium

5. Ca/P imbalance

what breeding related conditions can cause dental issues?

• inherited predisposition

• brachycephalic conformation

how do we measure rabbit acquired dental diseas?

• grading system 1-5

what is the progression of symptoms we see as rabbit dental disease gets progressively worse?

1. apical elongation

2. crown elongation and curvature

3. enamel spurs

4. acquired malocclusion

5. enamel hypoplasia

6. dental abscesses

what is apical elongation?

• what we see in rabbits with grade 2 acquired dental disease

• where eruption stops/slows due to reduced wear

what does apical elongation lead to?

• pressure on the nasolacrimal duct and nerves

• can lead to bone penetration

when asking owners about diet, what is important to be asking?

• how much is being eaten

  • WHAT IS BEING EATEN - anima could be eating lots, but only of pellets

what is acquired malocclusion?

• what we see with grade 3 acquired dental disease

• where the teeth change shape and position due to malocclusion

what does acquired malocclusion lead to with the teeth?

• crown elongation and curvature

  • enamel spurs

consequences of enamel spurs?

• soft tissue damage

• inflammation

• pain

what will happen with grade 4 acquired dental disease and why

• teeth stop growing - DON’T CONFUSE AS A GOOD SIGN

• this is due to destruction of germinal tissue

what will happen with grade 5 acquired dental disease?

• periodontal loosening leading to tooth rotation

• loss of alveolar bone which may cause abscesses

what views do we take for dental radiography?

• lateral - open mouth, closed mouth

• latero-oblique

• dorsoventral

1. what angle is this

2. is this normal

3. what structures can be identified?

1. lateral

2. yes

3. diastema = gap between incisors and cheek teeth, enamel folds, hard palate, tympanic bulla

What animals’ radiograph is this? How can we identify that?

1. chinchilla

2. flat, horizontal surface for the teeth, not bumpy like in rabbits

1. what view is this

2. what animal is this

3. is this a normal radiograph

4. what structures can we identify?

1. dorsoventral

2. rabbit

3. yes

4. cheek teeth, orbits, tempanic bulla - easy to spot any abnormalities!!

What abnormalities can we identify on this radiograph?

• incisors are incredibly overgrown of both the anatomical and reserve crown

• we have malocclusion which is severe

• the mandibular bone is deformed ventrally

roughly how large should incisors look on radiographs?

• 1/3 of a semicircle

what are indications for performing dental burring?

• incisory overgrowth

• cheek tooth overgrowth

what is the aim of dental burring?

• removing spikes/points

• restore normal anatomy

what are disadvantages of dental burring?

• not a long term solution

• need to find and treat the underlying problem

• not enough for abscesses

why may we extract teeth in rabbits?

• to reduce the stress of routine dental practice, reduce costs for owners and reduce anaesthesia risk

what is the difference between coronal reduction and spur removal?

coronal reduction = removal of entire exposed crown - no normal shape returned

spur removal = only remove spurs, rest is in tact

what does spur removal maintain that coronal reduction does not?

• the occlusal surface

what is the longest amount of time you’re allowed to burr for in one go?

• 5 seconds → gets too hot!!!

how can we prevent dental disease in rabbits and rodents?

• lots of grass and good quality hay

• only some pellets → NO MUSELI

• age, species and life stage feeding

• weeds, wild plants and fibrous veg

• only root veg and fruit as a treat

  • no sugary treats

what are 3 focuses for preventing dental disease

• encouraging gnawing behaviours

• selectively breed and cull

• good diet practice

what are some key clinical signs of dental disease:

1. anorexia and accompanied weight loss

2. reduced appetite

3. saliva staining

4. soft, sticky faeces = uneaten caecotrophs!!

5. mandibular swellings

6. halitosis

7. ocular symptoms

8. aggression - behaviour change

9. gut stasis (secondary to the dental issue)

10. oral wounds