A Novel Technique for Repairing Alveolar Clefts: Computer-Assisted Design With Posterior of Mandible Block Bone Grafts

Objective: Iliac cancellous bone graft is the gold standard for the treatment of alveolar clefts. However, the resorption rate of iliac cancellous bone is generally high. In this study, the authors propose a new method for repairing alveolar clefts using block bone grafts in the posterior region of the mandibular molar and the anterior margin of the ascending branch. Methods: Ten patients with a diagnosis of unilateral or bilateral alveolar cleft were collected. Block bone grafting between the posterior mandibular molar region and the inner and outer oblique lines of the anterior margin of the ascending branch was used to treat the alveolar synostosis. Preoperative, 1-week postoperative, and 6-month postoperative multislice spiral computed tomography scans of the patients were collected and analyzed for preoperative design and postoperative graft bone morphology using computer-assisted software tools, which were also required to measure the changes in the bone tissue density in the posterior mandibular bone extraction area. Results: At 6 months postoperatively, the mean bone resorption rate of the posterior mandibular bone grafts for cleft alveolar processes was 33.96% ± 11.23%. Bone tissue density in the posterior mandibular bone grafting area recovered to near preoperative levels at 6 months postoperatively. Conclusion: The novel method of bone grafting for the cleft alveolar process used in this paper is really effective. Postoperative posterior mandibular bone extraction did not cause sequelae such as mandibular bone defects or poor morphology in the patients. Computer-assisted design and three-dimensional printing technology helped to improve intraoperative bone grafting accuracy and postoperative assessment.