Prevalence of Periodontal Disease in Commercial Dog Breeding Facilities

February 24, 2018
JoAnna Pendergrass, DVM

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

Many experts believe that the dental health of dogs in commercial breeding facilities is poor, but researchers at Purdue University discovered some surprising facts.

Periodontal disease is a significant and common health problem for dogs in the United States. It is composed of gingivitis, which is reversible, and periodontitis, which is irreversible inflammation of the tissues that surround and support the teeth. Periodontal disease carries a serious risk of systemic disease, particularly cardiovascular disease. For dogs in commercial breeding (CB) facilities, this systemic disease can jeopardize healthy pregnancies.

In addition to annual professional dental assessments, regular tooth brushing and dental diets are key preventive care practices in dogs. In CB facilities, the prohibitive costs of professional dental cleanings and the risks associated with anesthesia make anesthesia-free dental care strategies like nonprofessional dental scaling (NPDS) appear more feasible. However, NPDS can cause pain and injury and is opposed by the American Veterinary Dental College (AVDC).


  • One Tooth at a Time
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Dental health is perceived to be poor in CB facilities. The Humane Society Veterinary Medical Association states that “severe periodontal disease is routinely seen in breeding stock…and is likely a result of poor diet, poor air quality/ventilation, and poor grooming practices.” To date, however, little empiric research has been done on periodontal disease prevalence in CB facilities.

Researchers at Purdue University recently addressed this important research gap and published their findings in PLoS ONE.


Researchers evaluated 445 adult dogs from 24 USDA-licensed, Amish-owned and -operated CB facilities in Indiana and Illinois. Two raters independently performed dental exams and determined periodontal disease score using the AVDC scale:

  • Grade 0: Healthy
  • Grade I: Gingivitis
  • Grade II: Early periodontitis
  • Grade III: Moderate periodontitis (eg, gingival recession)
  • Grade IV: Severe periodontitis (eg, infection, missing teeth)

Researchers also assessed body condition score, skull morphology (eg, brachycephalic), and dental care practices.


Overall periodontal disease prevalence was 86%, which is similar to the reported 80% prevalence for companion dogs; grade I disease was most common (44.5%). Although gingivitis does not always lead to periodontal disease and may overstate periodontal disease prevalence, reporting its prevalence in CB facilities is useful for assessing preventive care effectiveness and determining which dogs may need additional dental health monitoring, the researchers noted.

All CB facilities practiced preventive dental care, which frequently included chlorhexidine water additives, provision of a chew item, NPDS, or a combination of these practices. Also, all dogs in the CB facilities ate a commercial dry diet and received annual dental exams. Although the widespread use of preventive dental care strategies was encouraging, the researchers noted several concerns, including the unknown efficacy of chlorhexidine in water for reducing gingivitis and the risks associated with NPDS.

Age, facility, sex, and NPDS significantly increased periodontal disease risk, while provision of a chew item significantly decreased periodontal disease risk. Skull morphology and body weight did not significantly affect periodontal disease risk, which contrasts with previous studies reporting increased periodontal disease risk in smaller dogs.

Inter-rater agreement was moderate (86%), indicating room for improvement for training raters to use the AVDC scale for periodontal disease.

For the Future

These findings represent an important first step in objectively characterizing dog dental health in CB kennels,” the researchers concluded. For future research, they recommended evaluating the efficacy of chlorhexidine water additives and assessing periodontal disease in CB facilities with more diverse management practices. For the companion animal owner population, the researchers proposed more educational programs on the importance of preventive dental care.

Dr. Pendergrass received her Doctor of Veterinary Medicine degree from the Virginia-Maryland College of Veterinary Medicine. Following 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.