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E Q U I N E D E N T I S T RY — A N I N T R O D U C T I O N
Common dental abnormalities
Incisors
The most common condition is gingivitis with progression to periodontal disease caused by feed impaction in
the interdental space. Other common abnormalities include fractured or excessively worn teeth, presence of
malocclusions such as dorsal or ventral curvature (smile or frown bite) a slant bite (when viewed from directly
in front of the patient the incisor arcade slopes from one side to the other. Brachygnathism or prognathism
(parrot mouth or sow mouthed) an overshot or undershot jaw, Missing incisors, overcrowding, impacted teeth
or retained deciduous teeth. Lipping or hooks
Canine teeth
These teeth are unopposed and frequently collect plaque with associated gingivitis and gingival recession.
Wolf teeth
These teeth can be impacted or displaced and are frequently fractured during extraction due to poor technique
and equipment, proper removal should be done under local anaesthesia and involves elevation of the gingiva
and stretching of the periodontal structures to remove the tooth complete.
Cheek teeth
The most common abnormality is overgrowth of the cingulae (the vertical ridges on the buccal aspect of the
upper cheek teeth and the lingual surface of the lower cheek teeth) these are commonly referred to as sharp
points.
Malocclusions are common in the equine patient these include hooks (an elongation of the rostral aspect of
the first cheek tooth and the caudal aspect of the last cheek tooth.
Ramps are elongations that occupy more than 50 percent of the occlusal surface. Another common malocclusion
is a step mouth, this usually occurs when a tooth has been lost, fractured or impacted allowing the opposite
tooth in the opposing arcade to become overgrown. These teeth can dramatically affect rostro caudal movement
of the mandible and in some cases even cause ulceration to the gingiva and periosteal reaction of the opposing
arcade. A wave mouth is a form of malocclusion where some of the arcade (most commonly the 308’s 408’s
and 309’s and 409’s, 3 rd and 4 th lower cheek teeth) are over dominant of the opposing teeth. These teeth gradually
increase in height while there is a corresponding decrease in the clinical crown of the opposing teeth. The cause
of this condition has not been proven but in younger horses it is the authors opinion that this condition commonly
starts due the late eruption or impaction of the upper cheek teeth allowing the lower opposing teeth to become
over dominant. Wave mouth has serious effects on both lateral excursion and rostro caudal movement and leads
to other pathological conditions such as the formation of diastema and periodontal pockets between and
around cheek teeth.
Equine cheek teeth have ridges running transversely across the occlusal surface, these can become exaggerated
leading to impedance of rostro caudal movement and creation of diastema in the interproximal space. This
condition is much more common in stabled horses versus horses that graze continually
Retained caps or cap fragments, Equine deciduous premolars are shed between the ages of 18mths and
3yrs. These teeth can become impacted and fail to shed, this is one of the proposed causes of wave mouth (see
earlier) caps can also fracture leaving razor sharp sliver imbedded in the gum, impacted caps often have
associated feed impaction leading to gingival inflammation and infection.
Periodontal disease of cheek teeth is a common condition that is frequently poorly understood and diagnosed
in practice widening or diastema can form in the interproximal space leading to feed impaction with proliferation
of anaerobic bacteria and associated gingivitis and damage to the periodontal structures. This disease can