Engineering and Biomechanics in the Orthodontic Treatment of Periodontally Compromised Adult Patients

This study was undertaken to determine the optimal force system that should be used in the orthodontic treatment of periodontally compromised patients. For this we analyzed the biomechanics of the system formed by the reduced periodontal support - tooth - force delivered from the fixed orthodontic aplliance trough the bracket. The analysis of tensions was done by means of the finite element method (FEM) for a normal case and for reducing the periodontal support bone with 4mm. The force was applied in the center of the vestibular clinical crown (the L.A. point) and 3 mm more gingivally. The advantages of placing the brackets more gingivally are discussed. The manufactures of the bracket systems should improve their design in order to fit better for this clinical situations.