An update on periodontal disease in dogs (Proceedings)
Periodontal disease is probably the most common disease in dogs.1 Most dogs greater than 5 years of age have significant periodontitis. Periodontal disease increases significantly with increasing age, and decreases significantly with increasing body weight and is particularly obvious when comparing toy and small dogs with medium and large dogs.2 Periodontal disease is caused by the accumulation of bacteria in the form of plaque on the surface of the teeth which results in gingival inflammation and if left untreated results in the destruction of periodontal tissues which can result in clinically significant local and systemic problems. Periodontal disease occurs in two forms gingivitis and periodontitis. Gingivitis is a reversible inflammation of the gingiva. Periodontitis involves deeper inflammation with loss of tooth support and permanent damage. The purpose of periodontal therapy is to prevent gingivitis from progressing to periodontitis and to delay the progression of periodontitis once it is established.
Systemic antibiotics are not recommended for the routine prevention of periodontal disease, nor are they recommended for routine scaling of healthy dogs teeth without periodontal disease.4 However, perioperative antibiotics are recommended in animals with moderate to severe periodontitis, patients with painful oral ulcerations, animals who do not receive any home oral hygiene, those with systemic disease that may be worsened by bacteremia (turbulent blood flow caused by heart valve lesions or chronic renal failure), and patients undergoing concurrent clean or clean-contaminated surgical procedures.4 The antimicrobial of choice for clinical use in dogs with periodontal disease is Clavamox.3 The length of time recommended for the perioperative administration of antimicrobials varies from 2 to 10 days depending on the severity of periodontal disease. Perioperative antibiotics should be administered so that a therapeutic blood level is obtained prior to induction of the bacteremia caused by the dental therapy.
Stages of Periodontal DiseaseIn Stage 1 (gingivitis) periodontal disease, gingivitis with no attachment loss is present. Some dogs may have significant dental calculus with minimal gingivitis while others may have severe inflammation with minimal plaque and calculus. This stage of periodontal disease results in inflammation, edema, plaque and calculus accumulation, possible bleeding on probing, and possible pseudopocket formation.5 In Stage 2 (early) periodontal disease, the initial signs of destructive periodontitis are evident. Periodontal probing and radiographic examination may indicate attachment loss of up to 25%, teeth remain stable and pocket depths of 3-5mm are present.6 In Stage 3 (moderate) periodontal disease, the probing and radiographic signs of attachment loss are between 25% and 50% of the root length.6 Probing depths of 6-9 mm may be present with the presence of vertical defects and infrabony pockets. If gingival recession ispresent there may be only a minimal increase in probing depth indicating the importance of assessing attachment loss not only by pocket depth but also by measuring attachment loss from the cementoenamel junction to the depth of the periodontal pocket. Teeth may be mobile. In Stage 4 (severe) periodontal disease, the attachment loss is greater than 50%, there is severe loss of supporting tooth structures and pocket depths are greater than 9mm and teeth become loose. Significant infrabony pockets may be localized to a single area, such as the deep palatal pockets seen in maxillary canine teeth.
Diagnosis of the various stages of periodontal disease is based on a thorough oral examination, periodontal examination with a periodontal probe, and dental radiography. Animals with gingivitis, the reversible form of periodontal disease, have a swollen gingival margin that will bleed after the application of light pressure. Serous or purulent exudate is produced from the gingival sulcus. Halitosis is commonly present. Periodontal examination with a periodontal probe is normal and radiographically there is no evidence of bone loss around the teeth. Periodontitis in dogs is usually characterized by hyperplasia, gingival recession and pocket formation which progresses to tooth loss if untreated. Severe gingival inflammation with various amounts of calculus and debris are present with periodontitis. Periodontal probing will reveal the presence of periodontal pockets. Dental radiographs will reveal bone loss which is associated with periodontal disease. Bone loss may be horizontal or vertical. Horizontal bone loss is bone loss parallel to the cementoenamel junction which separates the anatomic crown from the anatomic root. Vertical bone loss is bone loss parallel to the long axis of the root.
Treatment of Periodontal Disease
Ideally the prevention of periodontal disease is preferred over the treatment of already established periodontal disease. Dogs can manage well without teeth, in fact dogs with very severe periodontal disease are better off without teeth because loss of diseased teeth is the most dependable way to eliminate this source of chronic infection.1 However, teeth should be retained whenever practical for functional and aesthetic reasons.1 It is recommended that occluding pairs of teeth particularly, the carnassial teeth or the canine (and maxillary third incisor) teeth be retained as functional units whenever practical. The treatment of periodontal disease includes a variety of techniques including: supragingival and subgingival scaling, root planing, subgingival curettage, polishing, gingivectomy, open-flap curettage and augmentation of boney defects, utilization of perioceutics, periodontopathogen vaccine, extraction, oronasal fistula repair, and home care.