P-66648670-167 - A study on load distribution in mandible with and without impacted third molars – A finite element analysis-based study

Abstract

<h3>Aim</h3> The objective of this study was to study stress distribution in the mandible with different positions and the presence of third molars with varying magnitudes of force and at various anatomical sites. <h3>Methods</h3> A patient-specific virtual 3d model was framed from DICOM images, and using ANSYS software, the virtual model was converted into an FE model. From this FE model, three additional models were created.: Model 1 with fully erupted third molar, Model 2 with impacted third molar, Model 3 with partially impacted third molar and Model 4 with missing third molar. Force magnitude of 1500N,2000N and 2500N was chosen to simulate trauma on symphysis, parasymphysis and angle. <h3>Result</h3> Von Mises stress was studied at bilateral condyle and bilateral angle. The relationship of variables was studied statistically using Bivariate analysis, and a statistical significance was fixed to p-value<0.05. There were no significant differences in stress among the four models at the condylar and angle region with the frontal blow. Von Mises stress at contralateral condyle was higher in Model 2, while stress at angle region was higher in model 1, on the same side of the impact in case of a lateral blow. The magnitude of stress increased linearly with the increased magnitude of forces at all four points. <h3>Conclusion</h3> The risk of angle fracture is higher in an erupted third molar, while the risk of condylar fracture is more in fully impacted third molars. Overall mean stress distribution followed Model 2>Model 1>Model 3>Model 4.