Análise comparativa do comportamento biomecânico de incisivos centrais superiores restaurados com núcleo metálico fundido e pino de fibra de vidro submetidos a movimentações ortodônticas: um estudo de elementos finitos

Abstract

This study aimed to analyze, using the finite element method, the biomechanical behavior of maxillary central incisors restored with glass fiber post (GFP) and cast metal post and core (CMP) submitted to buccolingual and mesiodistal orthodontic forces. Two maxillary central incisors were modeled, containing periodontal ligament, cortical bone and trabecular bone. In one of the models, an intraradicular restorage of GFP was included, and in the other model, one of CMP. After the creation of the tridimensional mesh of finite elements, the application of two orthodontic forces was simulated, one buccolingual of 65 g and another mesiodistal of 70 g. The forces were applied parallel to the palatal plan, in the slot of the bracket located 4 mm to the incisal edge. The maximum stresses generated in the GFP restored root were 3,642 x 10-1 MPa and 4,755 x 10-1MPa from the buccolingual and mesiodistal forces, respectively. Likewise, in the CMP restored root the stresses were 2,777 x 10-1 MPa and 3,826 x 10-1 MPa. The radicular area with higher stress on both models was located in the cervical third, considering the buccolingual force, that stress occurred on the buccal surface, and when the mesiodistal force was applied, it occured on the mesial surface. The CMP structure presented the highest levels of stress. The radicular stresses that come from buccolingual and mesiodistal orthodontic forces were lower on the CMP restored incisor. The post materials stresses were lower on the GFP structure.