Associations amongst three feline Porphyromonas species from the gingival margin of cats during periodontal health and disease

Abstract

Digoxigenin labelled whole chromosomal DNA probes directed against three feline members of the genus Porphyromonas ( P. gingivalis VPB 3492, P. circumdentaria NCTC 12469 T and P. salivosa VPB 3313) were used to identify and quantify organisms in samples taken from the gingival margins of 40 domestic cats with different grades of periodontal disease. At the right upper canine tooth, the grade of periodontal disease ranged from 0 to 5 and the cfu of facultative/obligate anaerobes ranged from 5.5 × 10 4 to 2.0 × 10 6). In 38 of the 40 cats, at least one of the three Porphyromonas species was isolated and regression analysis showed that the cfu of total Porphyromonas sp. was a highly significant indicator of the grade of periodontal disease ( p < 0.001, R 2 0.510). Feline P. gingivalis was isolated from 37 of the 40 cats and regression analysis showed that it was a highly significant predictor of the grade of periodontal disease ( p < 0.001, R 2 0.561). The cfu of P. salivosa was a significant predictor of the grade of periodontal disease ( p < 0.001, R 2 0.286) and regression analysis showed that there was a significant positive relationship between cfu of P. circumdentaria and grade of periodontal disease ( p = 0.018, R 2 0.116). The periodontal grades at the right upper third premolar tooth ranged from 0 to 6. The cfu of facultative/obligate anaerobes isolated ranged from 1.2 × 10 5 to 7.9 × 10 6, and regression analysis showed that cfu was a significant predictor of periodontal grade ( p < 0.001, R 2 0.378). The cfu of total Porphyromonas species ranged from 1.2 × 10 4 to 1.7 × 10 6 and regression analysis of the cfu against the grade of periodontal disease showed a highly significant association ( p < 0.001, R 2 0.633). The cfu of P. gingivalis ranged from 0 to 1.1 × 10 6 and regression analysis of the cfu of P. gingivalis against the grade of periodontal disease showed a highly significant association ( p < 0.001, R 2 0.439). The cfu of P. salivosa was a significant predictor of the grade of periodontal disease ( p < 0.001, R 2 0.479) and the same association was found between cfu of P. circumdentaria and grade of periodontal disease ( p = 0.002, R 2 0.204). This study has established Porphyromonas as a numerically significant and highly prevalent genus in feline periodontal disease.