Oral exams on awake veterinary patients: Waste of time or helpful tool?

April 4, 2019

Researchers examine effectiveness of visual assessment in screening for periodontal disease.

As any boarded veterinary dentist will tell you, the best way to determine the extent of periodontal disease in a veterinary patient is to conduct an oral examination under general anesthesia. What's more, this exam needs to include dental radiography of the entire mouth so that each tooth can be evaluated individually. But this approach, while considered the gold standard of care, is both time- and cost-prohibitive in a population-dense environment such as a shelter.

Enter the awake oral exam. It doesn't allow for checking under the gum line, so most experts say it's likely to miss all kinds of pathology, but it is still employed in situations where general anesthesia is not practical. In a recent study, one group of researchers compared the results of oral exams on fully awake patients with those of anesthetized patients to see if a visual assessment provided any value at all in detecting periodontal disease.

Their conclusion? “Proper use of visual assessment as a screening tool,” they say, “can help to identify the dogs at greatest need of dental care.”

Study details

The authors evaluated 108 dogs, aged 1 to 14 years, from three veterinary clinics: a referral dental practice, a small animal practice with a focus on dentistry and a community practice within a veterinary teaching hospital.

Each dog first received a fully awake visual assessment that included examination of the labial and buccal teeth surfaces, gingival margins, and mandibular teeth and gingiva. The veterinarian performing the assessment used the tooth with the worst periodontal disease pathology to determine a full-mouth periodontal disease stage using a five-point scale from the American Veterinary Dental College (AVDC) adapted for awake patients. For consistency's sake, a second veterinarian performed a visual assessment and determined periodontal disease stage as well.

Next, the dogs were anesthetized for dental radiography and a dental examination that included periodontal probing. The anesthetized procedures were termed the “reference standard,” and the veterinarian performing these procedures determined the disease stage using the full AVDC scale.

After the examination, the authors determined whether there was agreement between the visual assessment and the reference standard, as well as between veterinarians conducting the visual assessments.

Results

Overall, visual assessment agreed with the reference standard about 42 percent of the time. Agreement was strongest for stage 4 (55%) and weakest for stage 0 (17%). Notably, 25 percent of dogs classified as having stage 2 periodontal disease by the reference standard were misclassified as having stage 0 or 1 periodontal disease by visual assessment-such frequent misclassification as less-severe periodontal disease could lead to dogs receiving inadequate dental care. To counteract underestimation of disease severity, the authors recommended implementing veterinary dental management strategies for dogs at commercial breeding and long-term shelter facilities that have stage 1 or 2 disease according to visual assessment.

Consistency between veterinarians conducting visual assessments was 61 percent, indicating that visual assessment is a useful periodontal disease screening tool for fully awake dogs at population-dense facilities, the investigators concluded. The level of agreement increased with increasing disease stage, with 63 percent agreement for stage 4.

For stages where veterinarians were least consistent in their findings, additional diagnostics could help differentiate between gingival inflammation and bone loss, the authors suggested. For example, dissolved thiol is a biomarker that can be observed at the gingival margin. Whether commercial test kits that measure dissolved thiol are feasible for use in commercial breeding and long-term shelter facilities requires future study.

Moving forward

For the future, the authors suggested comparing veterinarians' findings on visual assessment with dental radiography results, given that such interpretation remains relatively subjective. In addition, because older and smaller dogs tend to have more severe periodontal disease, future studies could determine whether knowledge of a dog's age and breed could introduce bias when determining disease stage. Also, identifying key factors for improving dental care in population-dense animal facilities would be useful.

Link to study: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0203930

Dr. JoAnna Pendergrass received her DVM degree from the Virginia-Maryland College of Veterinary Medicine. After veterinary school, she completed a postdoctoral fellowship at Emory University's Yerkes National Primate Research Center. Dr. Pendergrass is the founder and owner of JPen Communications, a medical communications company.