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 gr afts in cleft palate patients, thus assessing the amount of bone necessary to facilitate eruption-especially in the buccopalatal direction-of the perm anent canine into the bone graft. Study design. Computed tomography scans taken immediately postoperatively a nd 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 seconda ry bone graft) or 12 years (late secondary bone graft) were compared. Three slices from the computed tomography scans taken immediately after the surg ery 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 r ank sum test. Results. In the unilateral cleft group, 70% of the transplanted bone remain ed in the cleft area after 1 year, whereas in the bilateral cleft group, on ly 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 eru ption of the permanent canine.