Effects of repeated scaling and root planing and/or controlled oral hygiene on the periodontal attachment level and pocket depths in beagle dogs. II. Bacteriological findings

Abstract

A study was performed to evaluate the effect of initial and/or repeated scaling with or without controlled oral hygiene on the level of periodontal attachment and pocket depth in beagle dogs. The clinical results of this three-year longitudinal study have been reported previously (Morrisson et al. 1979). The purpose of the present report is to present the microbiological results of subgingival plaque samples obtained from selected sites at the conclusion of the study. Eight beagle dogs with moderately developed periodontitis were divided into experimental and control animals. The experimental group received a thorough scaling and root planing at the start of the experiment following which the animals were subjected to daily toothbrushing and rubber cop and pumice prophylaxis every second week for 36 months. Four control dogs were not subjected to any oral hygiene procedures for the entire period of the study. The teeth of two quadrants in each animal of the experimental and control group were scaled and root planed every six months. After three years subgingival plaques from the mesial aspect of the fourth premolar in each of the quadrants of each animal were collected by sterile curettes, processed anaerobically, and cultured in an anaerobic globe box. Significantly lower total viable colony forming units (CFU) as well as significantly lower anaerobe/aerobe ratios were found in the subgingival plaques of the experimental animals. The total CFU of Bacteroides asaccharolyticus was 25 times of lower, and the proportion of CFU of this organism was nine times lower in the experimental sites when compared with the control sites. Repeated scaling every six months also lowered the total CFU and the proportion of Bacteroides asaccharolyticus in the subgingival plaques of the experimental as well as the control animals. The data suggest that the level of Bacteroides asaccharolyticus as key organisms as well as the anaerobic/aerobe ratio are valuable microbiological parameters in evaluating the efficacy of periodontal therapy.