抄録
Changes in alveolar bone following various periodontal surgeries were studied. The 55 surgical treatments were performed on 16 patients with periodontal disease. Radiographs were taken at the surgical regions by using the standardized X-ray technique. The interdental bone areas were measured on the X-ray films. The measurements were followed up to a period of three to four years. At the same time, various periodontal indices were also recorded. In addition, when a flap operation was performed, the type of bone defect was evaluated and recorded.
The results were as follows:
(1) Loss of alveolar bone was observed until 2 months after surgery and then new bone formation was observed,
(2) Among various periodontal surgeries, flap procedure demonstrated most bone loss post-operatively, gingivectomy showed moderate bone loss but following gingival curettage, apposition of new bone was observed 1 month after operation.
(3) Among various pattern of bone defects, the areas with horizontal bone loss showed an increase in bone apposition after 3 months post-operatively but in contrast the defect with one wall showed resorption of alveolar bone.
(4) The changes in alveolar bone were not correlated to the plaque index 10 months after operation, however 3 or 4 years postoperatively, the correlation between these two factors was significant statistically.
(5) The changes in the alveolar bone observed at an interval of 6 months and 3-4 years were found to be independent of the changes in the depth of periodontal pockets.
(6) The lamina dura re-appeared rapidly between 3-6 months post-operatively and then the rate of appearance levelled off at about 50%.
