Influence of plaque control on the healing of experimentally-induced bone defects in the dog.

The aim of this investigation was to induce alveolar bone defects experimentally in dogs and to study the effects of mechanical tooth cleaning on their subsequent development. Thirty premolars from four beagle dogs were used. Bone defects were created by surgically exposing the adjacent alveolar bone and applying steel or silk ligatures around the roots of the chosen teeth. After 8 weeks the ligatures were removed. Dental plaque was allowed to accumulate on 20 premolars whereas daily plaque elimination by toothbrushing was carefully performed on 10 premolars. After 1, 3, and 6 months of plaque accumulation, gingival inflammation, periodontal pocket depth, gingival recession and the radiographically observed degree of bone destruction were registered. Histological examination was performed in conjunction with the registrations made 6 months after removal of the ligatures. The clinical, radiographic and histologic findings all confirm that a regeneration of the experimentally induced destruction of the periodontal tissues had taken place. This reaction was most evident in teeth exposed to mechanical plaque control. The remaining bone defects were consistently accompanied by recession of the gingival margin.