ObjectiveTo investigate the clinical outcomes of resection of mandibular benign tumors and primary reconstruction with autogenous bone graft via an intraoral approach. MethodsFifteen patients with mandibular benign tumors were treated between January 2009 and September 2012. There were 7 males and 8 females, aged from 18 to 45 years (mean, 30 years). The pathological diagnosis identified 11 cases of ameloblastoma, 3 cases of odontogenic keratocyst, and 1 case of odontogenic myxoma. According to the Urken's CRBS (Condyle, Ramus, Body, Symphysis) classification criteria based on the location of the mandibular defect, there were 3 cases of body type (B type), 3 cases of ramus type (R type), and 9 cases of body and ramus type (BR type). The surgeries were performed via an intraoral approach, except 1 patient with the lesion at the level of sigmoid notch via an auxiliary preauricular incision. To fix the bone grafts to the dissected mandibular defects, reconstructive titanium plates were used, either indirectly according to the computer aided design/computer aided manufacturing mandibular models before surgery (9 patients) or directly according to the exposed mandibles during surgery (6 patients). The patients received benign mandibular tumor resection and primary autogenous bone graft reconstruction with free iliac bones (11 cases) or vascularized fibular flaps (4 cases). The mandibular inferior alveolar nerves were preserved in 6 cases. ResultsPrimary healing of incision was obtained in 14 patients, while secondary healing in 1 patient suffering from bone graft infection. All the patients were followed up 1-4 years (mean, 2.5 years). At last follow-up, no patients showed facial nerve damage; occlusion of remaining teeth was similar to preoperative conditions; the chewing function was satisfactory; mouth opening was 30-35 mm (mean, 33 mm); and swallowing and speaking functions were normal. Only slight extraoral scars caused by the auxiliary incision and the transbuccal appliances were observed, and all the patients were satisfied with the facial appearance. Lower lip numbness was relived in patients with preserved inferior alveolar nerves. There was no tumor recurrence during follow-up period. ConclusionThe intraoral approach is a feasible and proper approach for resection of benign mandibular tumors and primary reconstruction with autogenous bone grafts, with the advantages of inconspicuous facial scars, minimum damage to the facial nerve, and expectable aesthetic appearance.
ObjectiveTo evaluate the value of computer assisted navigation system (CANS) in the reconstruction of mandibular defects. MethodsBetween April 2012 and September 2014, 8 patients with mandibular defects were included in this study. There were 5 males and 3 females with an age range of 22-50 years (mean, 34.5 years), including 4 cases of ameloblastoma, 3 cases of odontogenic keratocyst, and 1 case of condylar osteoma. According to the CRABS (condyle, ramus, angle, body, symphysis) classification criteria based on the location of mandibular defect, there were 1 case of right CRAB type, 1 case of left RABS type, 1 case of left CR type, 1 case of right RAB type, 1 case of left C type, 1 case of right RABS+left S type, and 2 cases of right AB type. With the biteplate fixing mandible, maxillofacial CT and the donor site CT scan were done. Computer assisted design was made by using Surgicase CMF5.0 software and BrainLab Iplan software, included delineating the osteotomy lines for resection, ascertaining the normal anatomic structures for defect reconstruction, and determining the reconstructive morphology. With guide plates and the guidance of BrainLab navigation system, an en bloc tumor resection and simultaneous defect reconstruction were performed under the precise localization of mandibular angle and condyle. Preoperative and postoperative CT images were superimposed in Geomagic studio12.0 software system, and both were compared by three-dimensional (3D) objects and 2D slices. The complications and signs of recurrence were observed. ResultsUnder the guidance of navigation, preoperative facial symmetry design, surgery simulation, and simultaneous navigation operation were performed successfully. The postoperative CT and postoperative 3D error analysis showed osteotomy lines and reconstruction contour had good matching with the preoperative planning. The error of important corresponding points (mandibular angle and external pole of condyle) in the reconstruction of mandibular defects were (1.83±0.19) mm and (1.61±0.24) mm. The patients were followed up 2-6 months (mean, 3.5 months). No complication was observed in the other patients except the patients undergoing rib transplantation who had mild limitation of mouth opening. Good facial symmetry was obtained, and no tumor recurrence was found. ConclusionCANS can effectively increase the surgical precision in the reconstruction of mandibular defects and reduce complications, and recover facial symmetry. It is regarded as a valuable technique in this potentially complicated procedure.