Bone volume after secondary bone grafting in unilateral and bilateral clefts determined by computed tomography scans

Objective. The purpose of this study was to evaluate the outcome of bone grafts in cleft palate patients, thus assessing the amount of bone necessary to facilitate eruption-especially in the buccopalatal direction-of the permanent canine into the bone graft. Study design. Computed tomography scans taken immediately postoperatively and 1 year postoperatively of 42 unilateral and of 8 bilateral cleft lip and palate patients who underwent surgery at the age of 9 years (early secondary bone graft) or 12 years (late secondary bone graft) were compared. Three slices from the computed tomography scans taken immediately after the surgery were selected from the center of the bone graft and were then compared with corresponding slices from the 1-year postoperative computed tomography scans. Statistical analysis was performed by using the Wilcoxon 2-sample rank sum test. Results. In the unilateral cleft group, 70% of the transplanted bone remained in the cleft area after 1 year, whereas in the bilateral cleft group, only 45% of the initial bone graft remained after 1 year. Conclusion. No statistically significant difference was found between early secondary bone grafting and late secondary bone grafting. In most cases, a sufficient amount of bone was present in the target area to facilitate eruption of the permanent canine.