Spatial deviations of the temporomandibular joint after oncological mandibular reconstruction

Abstract

Spatial deviations of the temporomandibular joint (TMJ) after oncological mandibular reconstruction are important to the aesthetic and functional rehabilitation. The aim of this study was to clarify whether and how three dimensionally (3D) printed patient-specific surgical plates, and the preservation of the condyle or ramus, affect spatial deviations of the TMJ. A total of 33 patients who underwent mandibular reconstruction via computer-assisted surgery were included. Regarding absolute deviations, patients in the 3D-printed plate group showed smaller TMJ deviations compared to those in the conventional plate group. There was no difference in absolute deviations of the TMJ regardless of whether the condyle or ramus was preserved. Regarding physiological deviations, the impact on the contralateral TMJ was smaller in the 3D-printed plate group. Patients with both the condyle and ramus removed had significantly higher deviations of the condyle and joint space. In summary, 3D-printed patient-specific surgical plates improved the spatial accuracy of the TMJ. Under physiological conditions, TMJ deviations on the operated side were mainly affected by the preservation of the condyle. Removal of both the condyle and ramus caused more severe spatial interference to the TMJ; this should be further confirmed.

Deviation Analyses of Computer-Assisted, Template-Guided Mandibular Reconstruction With Combined Osteotomy and Reconstruction Pre-Shaped Plate Position Technology: A Comparative Study

“…In the 3D-printed plate group, greater impact of temporomandibular joint (TMJ) deviations were found on the lesion side than the healthy side. Moreover, patients without preservation of both the condyle and ramus had significantly higher deviations of the condyle and joint space ( 21 ). This result was consistent with our study.…”

“…Secondly, the deviations of the reconstructed mandible were assumed to be affected by the resection range, especially the posterior part of the mandible ( 24 ). The anatomical anchor of the fossa-condyle structure and the intact joint capsule stabilized the TMJ, and the masticatory muscles were mainly attached to the posterior mandible ( 21 ). Therefore, when the ramus was involved in the defect, the stability from the TMJ and the muscles greatly decreased, and reconstruction procedures became more complex at the same time, leading to increasing deviation.…”

Patient-Specific 3D-Printed Miniplates for Free Flap Fixation at the Mandible: A Feasibility Study

“…By subtracting the quality of fitting the corrected mean deviation was calculated. This resulted in a value demonstrating the absolute deviation ( 21 ).…”

The Precision of Different Types of Plates Fabricated With a Computer-Aided Design and Manufacturing System in Mandibular Reconstruction With Fibular-Free Flaps

“…A recent study by Yang and colleagues found that the use of CAS combined with a patient-speci c plate, speci cally a 3D-printed customized mandibular reconstruction plate, in non-extensive defects increases the spatial accuracy of the TMJ reconstruction, yielding better results than commercially available manually bending reconstruction plate 12 . Even though the patient-speci c plate can provide good results, surgeons may adopt different methods for bone xation processes such as miniplate and manually bending reconstruction plate.…”