Application of Combined Osteotomy and Reconstruction Pre-Bent Plate Position (CORPPP) Technology to Assist in the Precise Reconstruction of Segmental Mandibular Defects

Abstract Purpose To introduce and evaluate the clinical effects of digital surgical guide plate technology in the combined osteotomy and reconstruction pre-bent plate position (CORPPP) technique during mandibular segmental resections. Method Seven cases of segmental resections in mandibles with simultaneous vascularized free fibula flap reconstructions via oral and maxillofacial surgery were selected (Xiangya Hospital: June 2015-December 2015). Cone beam computed tomography (CBCT) and spiral CT scans of mandibles and fibular donor sites, respectively, were collected. Surgical simulations were conducted after data collection. Pre-bent titanium plates were emplaced within the predicted mandibular models. The samples were scanned via CBCT to obtain the positional relationships. Finally, CORPPP surgical guide plates with location holes were designed and fabricated on pre-bent titanium plates. The CORPPP surgical guide plates were applied in osteotomy and the emplacement of pre-bent titanium plates during surgery. CBCT scans were again conducted 2 weeks after surgery to examine the reconstructed composite models composed of mandibles and titanium plates. The scans were then compared with the preoperatively designed models. Additionally, the deviation of the integral and characteristic structure loci was analysed. Result The seven cases with emplaced pre-bent titanium plates exhibited good recovery in terms of occlusal relationships and the contour of the reconstructed mandibles. The absolute deviations in the integral analysis were 0.89±0.96 mm (mandibles) and 0.33±0.36 mm (titanium plates). The absolute deviations on the diseased side were as follows: 1.78±0.35 mm (condylar head), 2.43±0.29 mm (gonion), 2.22±0.22 mm (gnathion) and 2.66±0.36 mm (mesial inferior margin of the fibula). Conclusion The results of this study suggest that mandibular segmental resections and the precise orientation of pre-bent titanium plates could be simultaneously assisted by CORPPP digital surgical guide plates. The use of these guide plates should be expanded.