Tensão radicular em incisivos superiores: uma revisão sobre movimentação ortodôntica e restauração intrarradicular

Abstract

The objective of this study was to perform a literature review about the distribution of root stress in upper incisors during orthodontic movement and when restored with intraradicular posts. These posts are used to improve retention of restorative material on teeth with extensive coronary destruction. Both masticatory and orthodontic forces generate root stress. The finite element method is an accurate tool in stress analysis. During orthodontic treatment, factors such as root anatomy, position of the tooth center of resistance and type of movement, influence the way the stress is distributed along the root and periodontal ligament. For the restored teeth, the modulus of elasticity, the length, the diameter and the shape of the post, besides the cement used, are important characteristics in the determination of the stress in the post and the root dentin, as well as the susceptibility to the fracture. The most commonly recommended posts are those made of cast metal and of glass fiber. It has been found in the reviewed studies that materials with a modulus of elasticity close to dentin, such as glass fiber posts, contribute to a more homogeneous distribution of stress. Reducing post lengths can decrease root resistance to fracture. Posts with smaller diameter are less resistant, but excessive wear on the root canal during preparation should be avoided. There is a lack of studies that relate the teeth with posts with orthodontic forces.