Sensitivity of 2D and 3D analysis in swelling simulations of third molars extraction

Abstract

Two-dimensional (2D) techniques such as direct measurement, photography, or x-rays have been used to assess postoperative results of facial surgery, however, these techniques show limitations to analyzing three-dimensional (3D) surfaces. In this sense, facial scanning values, because it is possible to examine facial surfaces in 3D, represent an objective evaluation related to the results of maxillofacial care. Thus, this study will aim to analyze, through simulation, the sensitivity of different methods of evaluation of swelling after third molar extraction. Twenty volunteers will be selected and submitted to three methods of evaluation of swelling: 1) stereophotogrammetry (3D); 2) facial scanning (3D), and 3) manual measurements (2D). 3D images acquired before and after swelling simulation will be overlaid and a color map with numerical scale will be used to identify the distortion between the meshes. For 2D measurements, the percentage of facial edema will be calculated. The distortion values of the 3D meshes will be compared with the percentage of postoperative edema obtained by the 2D analysis, verifying the difference in the sensitivity of the methods. Quantitative data will be compared by correlation tests or multiple linear regression to identify the match or not among methods. All tests will be performed in the statistical program SigmaPlot 12.0, considering a significance level of 5%. (AU)