Periodontal diseases are the diseases of the tooth-supporting apparatus (periodontium) and are among the most common diseases of dogs and cats. The periodontium is a complex structure constituted by various tissues (gingiva, junctional epithelium, periodontal ligament, cementum, alveolar bone) that also maintains the integrity of the oral mucosa. Periodontal diseases are plaque-induced, usually chronic, inflammatory alterations of the periodontium. With the removal of plaque bacteria, gingivitis is a completely reversible disease.
However, if gingivitis is left untreated, it may develop in an irreversible destruction of the periodontium (periodontitis), including bone loss, and may lead to a loss of tooth function and ultimately tooth loss.
In contrast to gingivitis, periodontitis is only partially reversible. Periodontitis may develop very early in some breeds of dogs, and it is, in general, more prevalent in small breed dogs. The reasons for the progression of gingivitis into periodontitis are not fully understood, but an interplay between microorganisms and host response is likely to play a major role. With the development of supra- and subgingival dental plaque (biofilm), an increasingly pronounced inflammatory reaction is noted in the gingival tissue. When gingivitis progresses into periodontitis, a massive inflammatory infiltrate is noted histologically with progressive connective tissue attachment loss and bone resorption. Such findings are not always detected clinically upon examination of an awake animal, and, therefore, detailed oral examination under general anaesthesia with dental radiographs is mandatory to evaluate fully the extent and severity of periodontitis.
As per the American Veterinary Dental College (AVDC), there are five stages of periodontal disease. PD 0 describes clinically normal gingiva with no gingival inflammation or periodontitis clinically evident. This is, unfortunately, very rarely seen, apart in very young animals. Stage 1 (PD 1) indicates that there is gingivitis but without attachment loss. The height and architecture of the alveolar margin are normal. Stage 2 (PD 2) indicates early periodontitis with less than 25% of attachment loss or, at most, there is a stage 1 furcation involvement in multi-rooted teeth. There are early radiologic signs of periodontitis. The loss of periodontal attachment is measured either by probing of the clinical attachment level, or radiographic determination of the distance of the alveolar margin from the cemento-enamel junction relative to the length of the root. Stage 3 (PD 3) describes moderate periodontitis with 25-50% of attachment loss as measured either by probing of the clinical attachment level, radiographic determination of the distance of the alveolar margin from the cemento-enamel junction relative to the length of the root, or there is a stage 2 furcation involved in multi-rooted teeth. Moreover, stage 4 (PD 4) indicates advanced periodontitis with more than 50% of attachment loss as measured either by probing of the clinical attachment level, or radiographic determination of the distance of the alveolar margin from the cemento-enamel junction relative to the length of the root, or there is a stage 3 furcation involvement in multi-rooted teeth.
In general, PD 1 requires just basic periodontal therapy/professional dental cleaning with supra- and subgingival scaling and optional polishing, while teeth affected by PD 4 will need extraction. Teeth affected with PD 2 and PD 3 may be treated and kept for a while, providing daily oral home care is established, but the disease will generally progress.
If you have noted any problems with your animal, please consult your veterinarian.
Selected references
1. DeBowes (2010). Problems with the gingiva In: Niemiec BA (ed.). A color handbook of small animal dental, oral and maxillofacial disease. Boca Raton: CRC Press, Taylor & Francis Group; p. 159-181.
2. Girard N, Servet E, Biourge V, Hennet P (2009). Periodontal health status in a colony of 109 cats. J Vet Dent 26(3): 147-155.
3. Harvey CE, Shofer FS, Laster L (1994). Association of age and body weight with periodontal disease in North American dogs. J Vet Dent 11(3): 94-105.
4. Jakubovics NS, Kolenbrander PE (2010). The road to ruin: the formation of disease-associated oral biofilms. Oral Dis 16(8): 729-739.
5. Marshall MD, Wallis CV, Milella L, Colyer A, Tweedie AD, Harris S (2014). A longitudinal assessment of periodontal disease in 52 Miniature Schnauzers. BMC Vet Res 10:166. doi: 10.1186/1746-6148-10-166.
6. Ray JD Jr, Eubanks DL (2009). Dental homecare: teaching your clients to care for their pet’s teeth. J Vet Dent 26(1): 57-60.
7. Wolf HF, Rateitschak EM, Rateitschak KH, Hassel TM (2005). Color atlas of Dental Medicine: Periodontology. 3rd ed. Stuttgart: Thieme.
