Abstract
The purpose of this study was to evaluate the height of connective tissue reattachment from the bone margin after flap operation in monkey. 3mm or 1.5mm of crestal bone was horizontally removed at buccal and interproximal areas, and root planing was carried out completely. For a histological land mark, a notch was prepared on the root surface at the bottom of bone defect. Ten weeks after operation, the monkey was sacrificed. The periodontal tissues of 40 teeth in two monkeys were observed histologically. During ten weeks, efforts were made to keep oral hygiene as clean as possible.
The results which were obtained are as follows:
1) At molar areas which had slight gingival inflammation, connective tissue reattachment was clearly found. In the 3mm bone defect group, it was 2.22mm (S. D. 0.60), and in the 1.5mm bone defect group it was 1.56mm (S. D. 0.70). The mean amount of new cementum in the 3mm bone defect group was 1.06mm (S. D. 0.54), and in the 1.5mm bone defect group it was 1.00mm (S. D. 0.80).
2) At incisor areas which showed moderate gingi val inflammation caused by narrow attached gingiva, good connective tissue reattachment could not be obtained. In such areas, epithelial proliferation to apical site was found, but it stopped at the area where new cementum formation occurred. The mean amount of connective tissue reattachment was 0.90mm (S. D. 0.74) in the 3mm bone defect group and 0.85mm (S. D. 0.82) in the 1.5mm bone defect group. The mean amount of new cementum was 0.61mm (S. D. 0.39) in the 3mm bone defect group and 0.49mm (S. D. 0.39) in the 1.5mm bone defect group.
3) The mean amount of alveolar bone loss at molar and incisor areas was 0.11mm (S. D. 0.39) in the 3mm bone defect group and 0.35mm (S. D. 0.35) in the 1.5mm bone defect group respectively.
