Effects of oral hygiene on the results of periodontal surgery in beagle dogs with artificially created defects.

The effect of oral hygiene on periodontal surgery was evaluated clinically, radiographically and histologically during 24 months. In 13 beagle dogs artificial periodontal defects were created around the second, third and fourth premolars of the mandible. One week after removal of the plaque retention ligatures, periodontal surgery consisting of mucoperiosteal flaps and osseous recontouring was performed. Postoperatively, plaque accumulation was prevented by daily application of a 2% chlorhexidine solution for 2 weeks and daily toothbrushing for the next 2 weeks. Toothbrushing was continued in seven dogs; oral hygiene was discontinued in the other six. All dogs were scaled and polished at 1, 6, 12 and 18 months after surgery. Plaque accumulation in the nonbrushed dogs resulted in a heavy inflammation of the periodontium. Probing depths that had been reduced by the surgery increased and subsequently the clinical attachment level changed into a more apical level compared to the brushed dogs. Histometrically, however, no difference in attachment level could be recorded, indicating that oral hygiene did not affect the attachment level in the 2 years after surgery. It appears that oral hygiene stimulated bone formation and that the periodontal tissues had not matured in the 2 years after surgery.