Numerical study in biomodels of maxillofacial prosthesis (Cancer and osteonecrosis cases)

This work shows a methodology to successfully generate an anatomically appropriate mandibular prosthesis for two patients with different conditions affecting the bone: cancer and necrosis. A common technique for bio-modeling was used in both cases, which includes tomographic slices of 0.5 mm for each clinical case. As a result of the processing a stereolithographic model was performed using two different techniques, were the affected area was reconstructed. In the osteonecrosis case, with the use of auxiliary guide paths and drawings in the CATIA platform a 3Dmodel was produced, achieving a partial replacement with lateral support; while in the cancer case a left lateral replacement with the ramus was produced by reconstructing surfaces and patterns of the required area in PowerShape® and Solidworks® platforms. The region to replace was defined by the surgical expertise of a maxillofacial physician. Both cases were printed in acrylonitrile butadiene styrene (ABS) polymer producing a three-dimensional model, which was adjusted by the maxillofacial surgeon and subsequently integrated into a compound that includes cyanoacrylate with low toxicity, calcium powder, hydroxyapatite and isophthalic resin as a fundamental basis. The models were analyzed numerically using the same conditions that will be applied mechanically and clinically in order to obtain preliminary information on stress concentration zones and material deformation.