Equine 1 - Dentistry Flashcards
Which teeth in the horse are deciduous?
Incisors (x 3 per side)
Premolars (x 3 per side)
How many permanent incisors do horses have and what is their role?
3 per side
Prehend food
What are wolf teeth?
Vestigial first premolar, may have up to four. No role
How many permanent premolars and molars are in the equine mouth?
3 premolars and 3 molars per side which form one functional unit
If present, where are the canines found and what is their function
In the interdental space (between incisors and cheek teeth).
Possible fighting role
Define an anisognathus orientation, its purpose and drawback
mandibular jaw narrower than maxilla (slant of occlusal surface is 10-15 degrees)
Allows for effective grinding.
produces sharp edges over time
Define hypsodont teeth
high crowned teeth with enamel extending past the gum line
How much do equine teeth erupt per year?
2-5mm
Faster in younger horses than older
What may lead to dental disease in the horse
Disparity between eruption and wear
Around what age will equine teeth fall out?
25+ years old
Which teeth have their reserve crown in the maxillary sinus and what is the importance of this?
Upper 08-11
- 08/09 in rostral maxillary
- 10/11 in caudal maxillary
important regarding infection
Name the different types of calcified dental tissue and what they are secreted by
- cement - cementoblasts
- enamel - ameloblasts
- dentine - odontoblasts
name the different types of non-calcified dental tissue
- pulp
- periodontium
which dental tissue fills the infundibulum and covers the surface of the tooth that is secreted in response to growth and infection/injury
cement
which dental tissue is the hardest substance in the body, is inert and cannot repair itself
enamel
which dental tissue protects enamel due to its elasticity and compressibility and protects pulp by acting as a barrier
dentine
which two calcified dental tissues act as shock absorbers
cement and dentine
what is the role of pulp
supplies nutrition to the tooth
what is included in the periodontium
gingiva
periodontal ligament
alveolar bone
cementum
what is the function of the periodontium
shock absorber - enables the tooth to be firmly suspended within the alveolus while permitting a slight amount of movement
define buccal
the cheek side of the dental arcade or tooth
define labial
the tongue side of the dental arcade or tooth
define occlusal
the biting surface of the tooth
define apical
the tip of the root of each tooth
define mesial
towards the midline in a dental arch
define distal in terms of dentition
away from the midline in a dental arch
what is the interdental space
the space between the incisors and premolars in which the canines and wolf teeth lie
define diastema
a space or gap between two teeth
at what age do equine deciduous incisors erupt (D01-03)
D01 - 6 days
D02 - 6 weeks
D03 - 6 months
At what age do equine deciduous premolars erupt (D06-08)
all within the first 2 weeks of life
at what age to equine adult incisors erupt and occlude?
01 - 2.5yrs and 3yrs
02 - 3.5yrs and 4 yrs
03 - 4.5 yrs and 5 yrs
at what age do equine canines and wolf teeth erupt (if present)
canines (04): 4-5yrs wolf teeth (05): 6-18months
at what age do equine adult premolars erupt and occlude
06 - 2-2.5yrs and 3yrs
07 - 3yrs and 3.5yrs
08 - 4yrs and 4.5 yrs
at what age to equine molars erupt and occlude
09 - 1yr and 1.5yrs
10 - 2yrs and 2.5yrs
11 - 3-3.5yrs and 4 yrs
what is the most accurate method of aging a horse by dentition
eruption times
what shape will the corner incisor of a horse be when less than 10years old
wider than long
what shape will the corner incisor of a horse be when it is approximately 10 years old
square
what shape will the corner incisor of a horse be when it is over 10 years old
longer than wide
Name the methods of aging with dentition
eruption times shape of corner incisor dental star infubdibulum/mark disappearance galvaynes groove 'hook' on corner incisors shape of occlusal surface (oval --> triangular)
At what age does the dental star appear in equine incisors
01 - 5yrs
02 - 6yrs
03 - 7-8yrs
at what age do the cups disappear in equine incisors
01 - 6-7yrs
02 - 7-11yrs
03 - 9-15yrs
at what age does the mark wear out in equine incisors
01 - 12-15yrs
02 - 14-15yrs
03 - 14-15yrs
at what age does galvaynes groove appear then reach the full length of the tooth?
appears at 10yrs
full length of tooth by 20yrs
at what age does a ‘hook’ on the corner incisor appear in horses
7-13yrs
what should be included when gathering a dental history
- previous dental work
- previous dental problems
- feeding habits/behaviours
- bitting/ridden problems
what should be looked for during visual and manual exam of the head
- asymmetry
- swellings
- halitosis
- nasal discharge
- mastication observed (should chew in both directions)
how do you assess the caudal cheek teeth
full mouth speculum, light source and mirror
how wide is a normal lateral excursion of the jaw
width of 1.5 teeth, equal in both directions
why may it be necessary to examine equine teeth between 1 and 3 yo
- retained caps
- tumours of origin
- softer enamel
- quicker eruption
what should be looked for at an equine dental examination prior to bitting (3-4yo)
- sharp enamel points
- loose caps
- wolf teeth
- diastemata
how often should adult horses have a dental examination
every 6-12months
what should be looked for at an adult equine dental exam
sharp enamel points
step or wave development
diastemata
how often should geriatric horses have a dental exam (<15yo)
annually (more frequently depending on tooth alignment/disease)
what is the purpose of having open, straight and closed angle dental rasps
access every tooth
what material is used for the blades of dental rasps
tungsten carbide
what rasps are used for the lower cheek teeth
curved/gledhill
what is the function of picks and probes in equine dentistry
explore any defects/periodontal pockets
what is the risk of power tools in equine dentistry if used incorrectly
thermal damage
what restraint can be used for a dental exam
- full mouth speculum
- headcollar
- sedation
- stocks
what is the treatment of retained deciduous teeth and the problems associated with this
removal under sedation
can cause gap between incisors which may not close
may require radiographs if can’t tell which is the deciduous tooth (usually labial side)
what generally causes a fractured or displaced tooth
trauma - kick or getting tooth caught. therefore may want to radiograph to check for fractured jaw.
what are the possible treatments of a fractured tooth
extraction
wiring to stabilise
what does EOTRH stand for
Equine odontoclastic tooth resorption and hypercementosis
how does EOTRH present
affects older horses, causes resorption of roots +/- cementum deposition so teeth become loose and painful
how is EOTRH diagnosed and treated
diagnosed with x-ray
currently treated with extraction
missing, loose or overgrown teeth usually affect which horses?
usually older horses
occasionally abnormal conformation/development in younger horses
what is slant mouth and what causes it
incisor malocclusions (ventral/dorsal curvatures) leading to abnormal mastication secondary to cheek tooth disease
smile mouth is normal in which species
donkeys
what is parrot mouth
overshot jaw
what is sow mouth
undershot jaw
when does parrot or sow mouth require treatment
incisors which impinge on soft tissues
correction of secondary cheek teeth issues
correction as foal controversial if planning to breed from animal
what is diastemata
gaps which develop between the teeth, usually age related
how is diastemata managed
food picked out. can use old toothbrush
canine teeth are mainly found in which horses
males and dominant females
which conditions commonly affect canine teeth and when should they be removed
fractures and EOTRH.
remove due to calculus build up to prevent gum disease
how many wolf teeth may a horse have
up to 4 (2 upper, 2 lower)
when should wolf teeth be removed
- too large
- unerupted
- abnormally positioned
- lower
- fractured
- loose
- only on one side
- owner requested
why do sharp enamel points occur
anisognathic anatomy
continual eruption of teeth
eruption rate exceeding wear (diet)
why are domesticated horses predisposed to sharp enamel points
diet and lifestyle
where are the common sites of sharp enamel points
buccal aspect of maxillary teeth
lingual aspect of mandibular teeth
how are sharp enamel points treated and what happens if left
treated by reduction - routine dental work
if left will cause painful ulcers on the cheeks often upper 10/11
how should excessive transverse ridges be treated
reduced to normal height but not flattened completely
why do excessive transverse ridges need to be treated
can pack food into any diastemata
what are the causes of tooth overgrowth/overeruption
- developmental (asynchronous eruption)
- post-extraction
- post-fracture
- abnormal jaw alignment (parrot/sow mouth)
how does a maxillary cheek tooth root infection manifest in the horse
malodorous nasal discharge draining from a single nostril due to fluid build up in the sinus. may see swelling of the face and distortion of the facial bones. severe cases may see draining tract open on the face.
what is a common cause of quidding
diastemata
what are the causes of diastemata
- developmental
- increasing age - narrower towards root
- displaced/rotated teeth
what are the types of diastemata
valve - wider gap at level of gingiva so food becomes trapped and can’t escape
open - same width throughout
what is the treatment of diastemata
- balance mouth
- flush/pick out food
- pack with putty
- widen to allow food to escape
- remove tooth if severe
- pain relief/LA
- antibiotics
- revisit every 6 months
when may diastemata spontaneously resolve/symptoms improve
young horses - dental drift
older horses - become wider
what are the two types of caries
peripheral (surrounding edges of teeth usually towards the back of the mouth due to lack of saliva buffer)
infundibular (centre of upper cheek teeth potentially linked to tooth development and can lead to fracture)
how are peripheral caries treated
- remove sharp enamel points as smooth surface discourages food sticking
- flush if diastemata present
- modify diet (less acid/sugar)
- regular dental treatment to allow to grow out
how are infundibular caries treated
- filling affected teeth (specialist) to prevent future fracture
- removal if filling is not an option
what are the features of loose teeth in horses
- shorter overall length
- reduced periodontal attachment
- easier to remove (not always)
What are the causes of displaced teeth
developmental - overcrowding due to delayed eruption - last tooth struggles to erupt - hereditary acquired - abnormal occlusal surfaces - tooth loose in alveola
how are displaced teeth treated
- round edges so they don’t cause soft tissue ulceration
- flush out packed food
- ongoing management
what type of fracture is most likely to cause sinusitis and secondary infection
sagittal fractures in upper cheek teeth
how are tooth fractures investigated and treated
radiography
extraction (challenging)
what is shear mouth and its causes
abnormal increased angulation caused by eating on one side of the mouth (dental pain or conformation)
what is smooth mouth and its management
worn out cheek teeth generally seen in older horses or after overly aggressive dental work. can’t chew effectively so need dietary management
what is wave mouth and how is it managed
undulating occlusal surface. manual correction - don’t expose pulp of longest tooth and correct incisor length. may need multiple sessions
What is step mouth
lack of tooth leading to overgrowth of the caudal and rostral portions of opposing teeth which ‘lock’s the jaw
What causes wry nose
thought to be inherited but also malposition in utero
What are the signs and treatment of a cleft palate
dribbling milk after suckling and milk at the nostrils. surgical correction possible but often get complications
in what breeds is brachygnathism more common
TB and QH
in what breeds is prognathism more common
ponies and miniatures (achondroplastic dwarfism)
which conditions result from inappropriate differentiation of dental germinal tissue
missing teeth
maleruption
supernumerary teeth
which is the most common supernumerary tooth
fourth molar - erupts lingually or bucally if no room in arcade
name the types of congenital tumours and cysts
- ameloblastic odontoma
- juvenile ossifying fibroma
- dentigerous cysts
name the types of congenital/developmental defects possible in equine teeth
- parrot mouth
- wry nose
- cleft palate
- incisor malocclusions
- missing teeth
- maleruption
- supernumerary teeth
- tumours or cysts
name the basic dental techniques
- reduce sharp enamel points
- reduce dominant/overgrown teeth
- radiography
- tooth extraction
- sinus flushing/flaps
name the advanced dental techniques
- fracture repair
- wry nose correection
- ameloblastoma/tumour removal
- parrot mouth correction/braces
