RADIOGRAPHIC ASSESSMENT OF MANDIBULAR SYMMETRY FOLLOWING RECONSTRUCTION OF SEGMENTAL MANDIBULAR DEFECTS

Restoration of symmetric facial contours after resection of mandibular tumors is one of the requisites of a successful reconstructive surgery. For unilateral mandibular defects and using the “mirroring” feature available in many surgical simulation software, it is possible to restore the undistorted mandibular contours and bend the reconstruction plate prior to surgery.
The aim of this study: is to assess whether pre-bent mandibular reconstruction plates using computer-assisted techniques for post tumor-ablation defects are good enough at restoring mandibular symmetry radiographically.
Patients and Methods: eight patients with segmental mandibular post-tumor resection defects, to whom a computer assisted planning and pre-bending of the reconstruction plates were performed; were included in this study. For each patient, on the 3D reformatted image, a midsagittal plane was constructed and the perpendicular distances were measured from the midsagittal plane to the titanium reconstruction plate and to the contralateral intact side on the axial cuts. The mean differences calculated and statistically analyzed.
Results: The mean of the differences between the intact and reconstructed sides of the mandible showed normal data distribution. Overall mean among all patients was 0.7225 mm ± 0.24467. One-sample t test against a hypothetical mean difference of 0 mm revealed an extremely statistically significant difference between the intact and reconstructed sides with a p-value < 0.0001.
Conclusion: Computer-assisted precontoured mandibular reconstruction plates can be considered to offer a very good degree of symmetry during mandibular reconstruction procedures.