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
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detomidine 0.01mg/per kg and Butorphanol 0.02mg per Kg IV. Very fractious horses may require the use of
nerve blocks though these are usually reserved for horses needing treatment. Available blocks include the
zygomatic, the infraorbital, the mandibular and the mental.
Examination of the head
It is important to develop a systematic approach to examination, like other exams repeating steps helps to avoid
missing pathology. A suggested regime is to begin by assessing the temporal muscles looking at size, symmetry
and tone, then to look at the symmetry of the head and assessing the eyes for symmetry, discharge etc. Next
palpate the masseter muscles and the ramus of the mandible feeling for lumps, bumps, heat and pain. Gently
tap the region above the eyes to percuss the frontal sinuses and the region medial to the facial crest cranial to
the eye to percuss the maxillary sinus. Percussion of the normal sinus should result in the sound produced by a
hollow space a more muffled sound may indicate the presence of fluid or soft tissue in the sinus. Next visually
inspect the nares for inflammation and discharge and use your sense of smell to check for malodour. Facial
swellings, ocular asymmetry, discharge from the eyes or nasal passage can all indicate tooth root pathology and
should be investigated further.
Oral exam
Now part the lips and assess the lips, gingiva, incisors, tongue and bars of the mouth. Raise and lower the horses
head and view the incisors from one side of the horse to assess the rostro caudal movement of the mandible
accounting for breed differences the normal range of movement is between 2mm- 10mm.
Next shift the mandible to the left and to the right and measure the distance to molar contact, this is the point
at which the incisors begin to separate. A study of 730 horses found an average distance of 12.4mm with a
standard deviation of 3.1mm. By pushing the incisors 1 cm further trigonometric formulas are available to
estimate the angle of the cheek teeth arcades. Examine the gingiva for evidence of gingival recession, oedema,
bleeding, cuts etc and look for evidence of feed impaction between incisors. At this point the practitioner should
attempt to determine the approximate age of the patient based on dental markers.
The next step is to apply a full mouth speculum, clean the oral cavity and add a light source.
These devices are essential to allow diagnosis of common conditions. Begin the exam of the oral cavity, again a
systematic approach will yield the most consistent results. Some structures cannot be visualised from the front
of the horse and to see these will require the use of a dental mirror, intra oral camera or endoscope. Palpate
each tooth in the arcade and remove any food from the interproximal spaces, assess this food for the presence
of