Vertical ridge augmentation of atrophic posterior mandible with corticocancellous onlay symphysis graft versus sandwich technique: clinical and radiographic analysis

Alveolar ridge augmentation of atrophic posterior mandibular ridge represents a challenge in oral and maxillofacial surgery to restore aesthetic and function. The aim of the study was to compare the clinical and radiographic outcomes of bone formation in atrophic posterior mandibles augmented using onlay symphysis cortico-cancellous bone block with that augmented using sandwich bone augmentation technique (Inlay). Twelve patients were selected with missing mandibular posterior teeth. CBCT were done for all patients preoperatively to assess the residual bone height, ranged between 5 and 7 mm from the inferior alveolar nerve with adequate sufficient alveolar ridge width more than 4 mm. Patients required bone augmentation procedure with autologous onlay chin graft (group I) versus those used as inlay sandwich technique (group II). Clinical and radiographic analysis were done to analyses the newly formed bone and bone height. Percent of change in bone height was also calculated and revealed that group I was higher than group II, however, statistically insignificant differences between the two groups were found regarding the percentage of newly formed bone. Vertical ridge augmentation procedures using onlay chin graft took lesser time than the interpositional grafting with fixation technique, however, both techniques are promising for vertical ridge augmentation.