Colin E. Harvey

Periodontal disease in dogs. Etiopathogenesis, prevalence, and significance.

Periodontal disease is very common and often very severe in dogs. It is caused by accumulation of bacterial plaque, particularly Gram-negative anaerobic rods. Tissue destruction results from autodegradation induced by the continuing inflammatory response. Small dogs are particularly at risk. Prevention by retarding accumulation of plaque is the key concept.

Etiopathogenesis of Feline Dental Resorptive Lesions

There are several factors in the etiopathology of feline resorptive lesions. They may be considered as local immune-response mediating cell and humoral factors; release of biochemical components in dental and paradental tissues to attract odontoclasts; mechanical stress, including occlusal mechanism; and local and systemic calcium regulation, including remodeling of mineralized tissue and dietary intake of calcium.

Feline Dental Resorptive Lesions: Prevalence Patterns

Surveys were carried out in cats presented for dental examination in the Netherlands (432 cats) and in the United States (78 cats). In 62% of the Dutch cats and 67% of the US cats, resorptive lesions were present. In the Dutch study, Asian Short-hair (principally Siamese) cats were most commonly involved, and male cats were more commonly affected than females. The most commonly affected teeth were the fourth maxillary premolar and the mandibular premolar and molar teeth.

Association of periodontal disease with systemic health indices in dogs and the systemic response to treatment of periodontal disease

OBJECTIVE To determine whether severity of periodontal disease (PD) was associated with systemic health indices in dogs and whether treatment of PD altered systemic health indices. DESIGN Prospective cohort study. ANIMALS 38 dogs. PROCEDURES Healthy dogs with clinical signs of PD were included in the study. Physical examination, serum biochemical analysis, a CBC, urine evaluation, measurement of serum C-reactive protein (CRP) concentration, and a microalbuminuria test were performed prior to treatment of PD. All tooth roots were scored for gingivitis and attachment loss, and appropriate treatment of PD was performed. Laboratory data were obtained 4 weeks after treatment. The Spearman rank correlation and Wilcoxon signed rank test were used for statistical analysis. RESULTS Analyses of the correlation of several variables with attachment loss or gingivitis or of differences before and after treatment revealed significant results for several variables. After applying Bonferroni corrections for family-wise error rate, significant rank correlations were found between attachment loss and platelet number (r = 0.54), creatinine concentration (r = -0.49), and the within-dog difference in CRP concentrations before and after treatment (r = 0.40). The BUN concentration was significantly higher after treatment than before treatment. CONCLUSIONS AND CLINICAL RELEVANCE Increasing severity of attachment loss was associated with changes in systemic inflammatory variables and renal indices. A decrease in CRP concentration after treatment was correlated with the severity of PD. The BUN concentration increased significantly after treatment of PD. There is a need for continued research into the systemic impact of PD.

Association of periodontal disease, oral procedures, and other clinical findings with bacterial endocarditis in dogs

OBJECTIVE To identify risk factors potentially associated with the development of bacterial endocarditis in dogs and determine whether periodontal disease and surgical procedures (oral and nonoral) were associated with bacterial endocarditis. DESIGN Retrospective case-control study. ANIMALS 76 dogs with (cases) and 80 dogs without (controls) bacterial endocarditis. PROCEDURES Medical records were reviewed for information on signalment, physical examination findings, recent medical history, and results of echocardiography, clinicopathologic testing, and necropsy. RESULTS None of the dogs with endocarditis had a history of undergoing any dental or oral procedure in the 3 months prior to the diagnosis of endocarditis, and no significant difference was found between groups with regard to the prevalence of oral infection. Dogs with endocarditis were significantly more likely to have undergone a nonoral surgical procedure that required general anesthesia in the preceding 3 months or to have developed a new heart murmur or a change in intensity of an existing heart murmur. Preexisting cardiac dis-ease (congenital or acquired) was not found to be a risk factor. CONCLUSIONS AND CLINICAL RELEVANCE Results did not provide any evidence of an association between bacterial endocarditis in dogs and either dental or oral surgical procedures or oral infection. Findings suggested that the routine use of prophylactic antimicrobial administration in dogs undergoing oral procedures needs to be reevaluated.

Mapping of the Radiographic Central Point of Feline Dental Resorptive Lesions

Intraoral dental radiographs of 217 cats presented for dental treatment were examined. Radiographic signs of dental resorptive lesions were identified in 107 cats, and the apparent central point of each lesion was mapped on a diagram of the tooth. Mapping was only possible on maxillary and mandibular canine teeth and on mandibular third premolar, fourth premolar, and first molar teeth. Resorptive lesions were most common on the molar teeth (n = 103) and maxillary canine teeth (n = 96), and least common on fourth premolar teeth (n = 56). Resorptive lesions on premolar and molar teeth were widely scattered, noted more commonly in the coronal portions of the root. Resorptive lesions in canine teeth had a tendency to be located more apically on the roots.

Alendronate binds to tooth root surfaces and inhibits progression of feline tooth resorption: a pilot proof-of-concept study.

Tissue distribution, bioavailability, and efficacy of alendronate in preventing progression of resorption of teeth were evaluated in cats. [Butyl-4-14C-]-alendronate accumulates on subgingival tooth and alveolar bone surfaces adjacent to vascularized tissue resulting in concentration of the drug around tooth roots. Three cats were treated with a 0.03 mg/kg IV bolus of [butyl-4-14C-]-alendronate followed by blood, urine, and feces collection and euthanasia 24-hours later. Drug tissue distribution was accessed by autoradiography and sample combustion. To assess bioavailability, 12 cats were administered alendronate orally (3.0 or 9.0 mg/kg in water or 9.0 mg/kg in tuna water) and urine was collected for 24-hours. In these formulations, alendronate oral bioavailability in cats was approximately 3 %. In addition, 10 cats with radiographic evidence of pre-existing tooth resorption (14 affected teeth) were treated with vehicle or 3.0 mg/kg alendronate per os once weekly for 22-weeks and, then, 9.0 mg/kg per os twice weekly for 27-weeks in a random, masked study. Radiographic area of resorption was measured and progression scored every 3 to 4-months. In placebo-treated cats, resorption progressed in five of six teeth (+ 97 % average increase in area of resorption), whereas progression of resorption was seen in only three of eight affected teeth in alendronate-treated cats with a – 22 % average change (decrease) in area (P < 0.01 difference in number of teeth showing progression; P < 0.001 difference in area of resorption). Alendronate accumulated preferentially on subgingival tooth surfaces and adjacent alveolar bone and, at a dose of 9 mg/kg twice weekly, effectively slowed or arrested the progression of resorption.

Shape and size of teeth of dogs and cats-relevance to studies of plaque and calculus accumulation.

Crown width, height and buccal surface areas were measured on heads or skulls of four dogs and four cats, and were compared with similar measurements on models of human dentition. Buccal surface area variability was greater in dogs and cats than in humans, and teeth of cats were smaller. Horizontal (gingival and occlusal halves) and vertical (mesial, middle, and distal thirds) buccal surface area variability was also greater in canine and feline teeth compared with human teeth. This increased variability suggests the need for testing of reliability and repeatability of scoring when using plaque and calculus indices based on horizontal or vertical segmentation. Buccal surface area variability between teeth also prompts questioning the validity of equal weighting of smaller, irregularly-shaped teeth when calculating a mean mouth score. Whether equal or more reliable results would be obtained from scores of whole teeth in comparison with segmentation indices used currently has yet to be determined.

Feline Oral–Dental Radiographic Examination and Interpretation

This article describes the technique of taking intraoral radiographs and developing film. Interpretation of oral radiographs is described. Radiation safety is reviewed. A troubleshooting section is included.

Scoring the full extent of periodontal disease in the dog: development of a total mouth periodontal score (TMPS) system.

The development of a total mouth periodontal scoring system is described. This system uses methods to score the full extent of gingivitis and periodontitis of all tooth surfaces, weighted by size of teeth, and adjusted by size of dog.