Comparison of block bone and sandwich bone graft from posterior region of mandibular molar for alveolar cleft repair: A retrospective study.

This retrospective study was designed to assess the efficacy of alveolar cleft reconstruction using bone grafts derived from the posterior region of the mandibular molar and to compare the osteogenic properties between block bone grafts and sandwich bone grafts (a structure consisting of "cortical bone + cancellous bone + cortical bone"). A total of 22 patients were involved and divided into two groups based on the type of bone graft used. The primary outcome measures included the assessment of cleft region volume, filling rate, osteogenesis rate, and resorption rate at six months postoperatively. The results indicated that the volume of the core cleft region significantly influenced the filling rates, with a linear relationship observed between the filling rate and osteogenesis rate (p < 0.001). The sandwich bone graft group demonstrated a higher filling rate (82.89 % ± 11.14 %) compared to the block bone graft group (70.40 % ± 9.05 %). The type of bone graft had a significant impact on the osteogenesis rate at six months postoperatively, while resorption rates were similar between the two groups. In conclusion, bone grafts derived from the posterior region of the mandibular molar show great potential for alveolar cleft reconstruction. Sandwich bone grafts may offer superior filling and osteogenesis rates, particularly in smaller clefts. However, the volume of bone available from the mandibular molar region may limit its application in larger clefts.