Clinical feasibility and efficiency of a 3-dimensional printed surgical template for mandibular angle osteotomy and mandibular angle splitting osteotomy.

Mandibular angle osteotomy (MAO) and mandibular angle splitting osteotomy (MASO) are the two main surgical approaches used to correct a square mandible for a desirable aesthetic appearance. However, there are concerns about the safety and accuracy of both procedures as they may lead to unsatisfactory results such as injury to the nerve. To achieve symmetry and security we designed and evaluated a 3-dimensional printed surgical template, which indicates the outer cortex splitting line of the MASO, and the curved cutting line of the MAO. We operated on 11 patients who had been diagnosed with broad mandibles using the assisted template. The mean duration of osteotomy, degree of numbness of the inferior alveolar nerve, and reduction in the width of the mandible (Go-Go) were recorded. The mandibular curve before and after operation was fitted to evaluate its accuracy. The results showed that mean duration of osteotomy and numbness of the nerve were reduced, and there was no significant difference between simulation and postoperatively. The mean (SD) reduction in the mandibular width was 15.2 (1.6)mm. The template facilitated accuracy and safety in both procedures.