What is periodontal disease in dogs?

Periodontal disease is the destruction of bone, gum tissue, and other structures that surround and support the teeth. Bacterial infection and the development of biofilms on the teeth play a key role in the progression of this disease. Periodontal disease is classified into four main grades, with Grade 0 indicating the absence of disease.

Stages of Gum Disease in Dogs

Grade 1:

The early stage of periodontal disease begins with films of plaque and tartar containing bacteria building up within the mouth, causing redness and inflammation of the gum tissue (gingivitis). At this stage, the infection is acute and superficial enough that there is no secondary bone loss. This stage is reversible with professional cleaning and periodontal therapy.

Grade 2:

As the disease progresses, the gingiva and surrounding tissues become increasingly inflamed and may appear swollen. Although there may be no obvious visible changes at this stage, oral radiographs will reveal mild bone loss (less than 25%) around the affected teeth.

Grade 3:

With further advancement, early signs of gum recession may become apparent. Chronic inflammation and infection cause the gums to recede, making the teeth appear longer as the gum tissue pulls away from the crown. Bone destruction progresses, with 25–50% loss of attachment to the tooth.

Grade 4:

In the final stage, there is significant destruction of the gum tissues and secondary exposure of the tooth roots. Bone loss exceeds 50%, leading to instability and mobility of the affected teeth.

Treating Periodontal Disease in Dogs

Each tooth in your pet’s mouth may be at a different stage of periodontal disease and must be evaluated both clinically and radiographically for an accurate diagnosis. Teeth in the early stages (Grades 1–2) can often be treated and reversed with periodontal therapy. Teeth affected by Grade 3 disease may require advanced procedures along with dedicated home care and regular professional dental cleanings. Teeth in Stage 4 almost always require extraction.

Schedule an Exam with a Houston Dog Dentist

If you have questions about periodontal disease or are concerned your pet may be affected, please call our office to schedule an oral examination with one of our veterinarians.

Images used under creative commons license – commercial use (6/9/2025). Photo by Vidak on Unsplash