New Approach for Virtual Surgical Planning and Mandibular Reconstruction Utilizing the Occipital Crest as a Native Midline Landmark

Abstract

Virtual surgical planning (VSP) using computer-aided design and manufacturing (CAD-CAM) has been reported to aid in craniofacial reconstruction. The reported improvements have been related mainly to operative performance, with limited evaluations of the position and function of the temporomandibular joint (TMJ). This study analyzed the radiographic details of postoperative outcomes of mandibular reconstruction related to the TMJ as well as the mandibular Gonion angles utilizing the external occipital crest of the cranial base as an alternative to the sagittal plane for mirror image purposes. The patient initially presented to us with massive disfigurement with a counter-clockwise rotation of the condyle bearing segment of the affected side apparently under the effect of the temporalis muscle with a limited mouth opening and deviation while opening. Post-operative (virtual planning) were analyzed to compare the condyle segment with the previous position as well as the angles of the mandible The virtual surgical planning utilizing the cranial base triangle gives a better position for both the condyle and the angle with a more symmetrical position and the condyle in more favorable position within the glenoid fossa. The external occipital crest is a native midline landmark that could be utilized as an alternative to the sagittal plane for a mirror image in mandibular reconstruction with all the hereditary errors that are sensitive to the position of the sagittal plane virtually. This case report shows a better condyle position with virtual surgical planning versus the traditional method of reconstruction.