Computed tomographic evaluation of bone formation after secondary bone grafting of alveolar clefts

Purpose: The purpose of this article was to evaluate the initial volume of alveolar clefts and the bone bridges formed in patients who had undergone s econdary bone grafting. Patients and Methods: Fifteen cleft patients were studied. Computed tomogra phy (CT) scans were made at 2-mm slice sections immediately before operatio n and at 3 months and 1 year postoperatively. The volume of the alveolar cl efts and bone bridges was calculated from stored images by using an image s canner and a personal computer. Results: The mean cleft volume of the patients was 1.1 +/- 0.3 cm(3). The c orresponding volume of the bone bridges 3 months and 1 year postoperatively were 1.2 +/- 0.6 cm(3) and 1.1 +/- 0.5 cm(3), respectively. The value at 1 year was significantly decreased compared with that at 3 months. Conclusions: Adequate bone bridging was maintained for 1 year. However, it is suggested that the grafted site should be restored with a functioning to oth or a dental implant to place it under physiologic stress, because the v olume of the bone bridges tends to decrease from 3 months to 1 year.