Virtual surgical planning for mandibular ramus distraction osteogenesis

Virtual surgical planning (VSP) is becoming a standard procedure in managing patient indicated for distraction osteogenesis as part of the surgical management. In general, the use of VSP is not part of the routine treatment protocol due to the high cost and steep learning curve associated with it. In this case report, we would like to share our experience in managing patients with hemi-micrognathia secondary to ankylosed temporomandibular joint via distraction osteogenesis. Preoperatively, the patient's Digital Imaging and Communication in Medicine (DICOM) is used to create a stereoscopic simulation image. The ramus distractors were scanned to create a virtual ramus distractor. All this data is then appended into the software to decide on the osteotomy site as well as vector placement of the distractors virtually. This allows for virtual simulation of the proposed surgical plan. Once the osteotomy site and the vector for the ramus distractor has been finalised, a hybrid guide is created to aid in both osteotomy as well as identifying the vector for the distractor. Post-operatively, distraction devices were activated twice daily until distraction length was achieved followed by a consolidation period. VSP and hybrid guide allows surgeons to better understand the pitfalls of the case, simulate multiple possibilities virtually and also a as a good communication tool during patient consultation.