Menzies says he goes over each tooth in the lingual and palatal aspect, occlusal surface and vestibular surface, paying particular
attention to the interproximal area where diastemata form and food is entrapped (Photos 2A & 2B). Image capture software allows
each view to be recorded. "If there's impacted food, it's best to try to get that out before doing endoscopy because it might
obscure certain areas," he says. "It might help to use a high-pressure Waterpik and an explorer to get the food out to more
properly examine the teeth and periodontium."
Photo 2A: Entrapped feed in a diastema between the left mandibular third and fourth premolar teeth.
After the endoscopic examination, go back and check any areas of concern, Menzies says. Palpate each tooth, and apply percussion
or heat and cold. As you apply these provocation tests, look for repeatable responses from the horse, which are possible even
with the effects of sedation and analgesia already administered.
Photo 2B: The same diastema in Photo 2A with the feed removed revealing marked periodontal disease.
"Often I'll take a heavy probe to tap on the teeth or lightly push on them to see if there are any loose teeth," Gregory says.
"I also inspect the gingiva, both on the vestibular and palatal sides, for discoloration and pockets. I look at the palate,
gums, salivary ducts and tongue. Once I get to that point, I move the speculum down to manipulate the mandible, looking for
excursions of overcontact, abnormal sounds or squeaking, as an abnormal tooth has a high pitch."
During the examination, Gregory periodically stops to record what he has done, though the endoscope has the ability to record.
He also may take photographs, depending on what he finds. "For 50 to 75 percent of the horses I see, I recommend radiographs.
I take x-rays and put that together with what I see visually."
Menzies agrees that if areas of concern are found, radiography is the most appropriate next step because most information
lies below the gingiva. "It's a challenge because oral radiographs are not the easiest radiographs to do or to interpret.
The better your radiographs are, the easier it becomes to diagnose. Though it can be tricky for the neophyte, you really can't
do a proper diagnosis without radiography."
Further imaging using computed tomography and scintigraphy can be helpful, he continues, particularly for certain types of
fractures and for tumors, especially those of the maxilla.
Oral health just a part of the whole
Menzies notes that veterinarians shouldn't hesitate to refer cases to dental and other specialists when needed. "No one is
the ultimate expert, but we can all help out," he says. "We each have varying levels of expertise that are complementary.
A horse suspected of an oral problem could end up needing the skills of a radiologist, an internist, an ophthalmologist, a
surgeon, an anesthesiologist, a histopathologist, a microbiologist, a parasitologist or a behaviorist—just to name a few—besides
those with extra training in dentistry."
A horse's systemic health is important to determine, he continues. For example, conditions such as Cushing's disease may have
a marked influence on oral health. "Cushing's affects the body in many ways. In the mouth, the abnormal collagen metabolism
decreases immune function and impairs healing abilities. Horses with Cushing's tend to have loose teeth, periodontal disease
and a disproportionate amount of oral ulcers. When you're treating a horse with Cushing's for periodontal disease, it's a
good idea to treat the Cushing's as well. That's certainly one reason I feel so strongly that dentistry is a veterinary-only
activity; the oral health cannot be considered in isolation from the rest of the body."
Ed Kane, PhD, is a researcher and consultant in animal nutrition. He is an author and editor on nutrition, physiology and
veterinary medicine with a background in horses, pets and livestock. Kane is based in Seattle.