Equine Dentistry Flashcards
What teeth do horses have and how are they named simply?
Incisors
Canines
Wolf Teeth (P1)
Cheek teeth (P2-P4 & M1-M3
What type of teeth do horses have?
Hypsodont (high crowned teeth with enamel that extends past the gum line)
Describe the chewing motion of a horse, including where pressure is applied.
Horses have a lot of lateral movement at the TMJ. Their mastication occurs in a figure of 8 motion and consists of an opening stroke, closing stroke and power stroke which is where major pressure is applied at one side at a time!
What do the following teeth numbers correspond to? Give the arcade and the tooth.
a) 105
b) 301
c) 502
a) Right top wolf tooth
b) Bottom left first incisor
c) Decidous tooth is preceded by the number ‘5’
note: The first number indicates the arcade and the second number indicates the tooth. The numbers go from 1-4 top right-bottom right (topR topL bottomL bottomR i.e. clockwise)
Why can a horse only grind on one side of its mouth at a time? What other adaptations of the mouth, with respect to arcade angles, are there?
The horse has anisognathism which means the maxillary arcade is wider than the mandibular arcade.
The occlusal surface is 10-15 degrees in angle and the teeth curve upwards at the caudal aspect which is called the ‘curve of spee’.
What are the normal components of a tooth? Describe a difference in these components between maxillary, mandibular and incisor teeth in the horse
Cementum - holds the tooth to the peridontal ligament.
Enamel - hardest part of the tooth, laminated sheets
Dentine - makes up the bulk of the tooth, tubular structures
Infundibulum - infolding of enamel from the occlusal surface (full of cementum)
Pulp - blood and nerve supply
Maxillary teeth have 2 infundibulae
Mandibular have none
Incisors have 1
What is important to bear in mind when filing a horses tooth?
Horses have secondary dentine which normally protects the pulp and its movement down towards the root is stimulated by wear. Excessive filing of the teeth may expose the pulp which is counterproductive.
When might one perform an equine dental exam?
Annually - prophylaxis Specific problems - -Swellings/discharge -Weight loss -Quidding -Headshaking -Biting problems -Unilateral nasal discharge
What is quidding?
Taking in food, chewing but then spitting out the bolus. Would see a bile of half chewed boluses on the floor of the stable.
How is a dental examination performed?
Observe (eating) Other physical exam (e.g. BCS) Head exam (see lect for more info!) Oral -incisors -interdental space -cheek teeth
What things are needed for an equine dental exam?
- Restraint/Sedation - if possible as gives a better idea of back of the mouth
- Support head
- Illumination
- Gags
- Dental chart
What aids are there to diagnostic of dental problems?
Mirrors Picks Oral endoscope Radiography Scintigraphy CT
What should teeth cheek teeth be examined for?
Buccal/lingual points/ulceration Deciduous caps/remnants Focal overgrowths Molar table angle Wave mouth Step mouth Fractured teeth Diastema Excessive transverse ridges Foreign bodies Periodontal disease Caries
What aspect of the diet can lead to ‘point’ formation?
Chewing concentrates as this encourages a vertical chewing motion rather than a lateral chewing motion. Enamel overgrows and ulcerates parts of the mouth
What is ‘shearmouth’?
This is when the occlusal surface is greater than 15 degrees, it results from severe enamel overgrowth.
How can shearmouth be treated?
Reduce buccal and lingual points
Reduce angle starting at the high side.
Treat regularly and
Treat underlying problems
What are the different types of rasp blade and their disadvantages/advantages?
Carbide chip - Cheap but robust and ok for routing work but harder to remove hooks
Tungsten carbide blades - expensive and brittle but excellent. Better for removing hooks than carbide chip blades
What are the basic types of rasp needed for routine work?
Straight head long length
Obtuse angle with length
Angled offset head of medium length
S float
What care needs to be taken when using power tools for rasping?
The palatine artery! This runs 1cm medial to the upper cheek teeth!
How should remaining deciduous teeth be dealt with?
Remove with forceps or a screwdriver but be careful not to damage the permanent tooth behind it!
How do rostral and caudal overgrowths develop? Which teeth is this referring to (use number)?
Usually due to the rostral displacement of the maxillary arcade (parrot mouth). Affects 106, 206, 311, 411
How can hooks be distinguished from the curve of spee?
Run a finger over the back of the tooth to the gingiva behind it and if it feels sharp then it is a hook.