Immediate Reconstruction of Benign Pathology Ablative Defects with Non-vascularized Bone Grafts
This study evaluates the success and utility of immediate reconstruction of mandibular bony defects post ablative surgery for treatment of benign tumors and lesions as opposed to traditional primary resection with delayed secondary reconstruction. In addition, a planning protocol is presented with use of stereolithographic models that allow for accurate resection, hardware adaptation and immediate reconstruction
Materials and Methods
17 Patients who presented with an advanced ameloblastoma (12), odontogenic myxoma (2), osteoblastoma (1), AVM (1), or central ossifying fibroma (1) involving the mandible were treated with resection and immediate reconstruction using anterior iliac crest bone graft. The age of the patients ranged from 9-63 years with the mean age 28.1 years. Computer tomography images were obtained in all cases to accurately evaluate the tumor extent and for fabrication of stereolithographic models. All resections were planned with one centimeter bony margins. Ablative defect size ranged from 3cm to 10cm with a mean size of 7.23cm. When soft tissue involvement was evident, resection to the next anatomic layer was undertaken following basic oncologic principles. Accurate planning of tumor resection and adaptation of the reconstruction plates as well as measurement of the anticipated bony defects was done on the stereolithographic model pre-operatively. All resections and reconstructions were done entirely intraorally thus completely avoiding extraoral incisions including stab incisions for transbuccal trocar which was not employed. In all cases intra-operative imaging of the specimen was utilized to confirm the presence of radiographically disease free margins of several millimeters.
Results
Of the 17 immediate reconstructions performed, 1 has failed to date (osteoblastoma) giving a success rate of 94%. Follow up has ranged from 1 to 61 months. 7 patients to date have had dental implants placed, 2 have declined implant placement. Apart from the single failure no wound infections have been encountered. 1 patient experienced a minor wound dehiscence which was managed with local wound care and subsequently underwent successful implant placement.
Conclusions
With the high demand for immediate functional rehabilitation and when resection does not cause extensive soft tissue defects, our approach of immediate bony reconstruction is highly desirable. It allows for timely rehabilitation and minimizes complications associated with two stage procedures as well as avoiding extraoral incisions and subsequent scarring. The use of stereolithograhic models for pre-operative planning and hardware adaptation in addition to increasing accuracy and allowing for improved facial symmetry to be achieved, significantly decreases operative time. Potential complications from multiple surgical procedures, delayed secondary reconstruction, repeated general anesthetics, and the financial burden of multiple operations can be avoided with this approach.
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