Estudo comparativo da dissipação de forças e eficiência entre o aparelho de Hyrax e o aparelho de Battistetti através de análise por elementos finitos

Abstract

Surgical assisted rapid maxillary expansion (SARME) represents an important topic in Oral and Maxillofacial Surgery. This surgical method is described for transverse maxillary corrections in patients with completed bone formation, or failure obtained with the non-surgical method of disjunction of the maxilla. There are several techniques and devices associated with SARME, the most famous are the Hyrax and Hass disjunctor, which are tooth-borne and tooth-muco-borne respectively. Bone-borne devices are also described in the literature and have the advantage of direct transmission of the forces to the maxilla and not to the teeth. Its main disadvantage is the cost that makes it impossible to most of the treatments. The device developed by Battistetti et al. (2010) translates into a custom bone-borne disjunctor, made from a lathe and two steel plates fused by a silver solder and fixed to the bone by two screws on each side. It has all the advantages of a conventional bone-borne device with much lower cost. The aim of this study is to evaluate the transmission of forces and efficiency of Battistetti device and make a comparison with the Hyrax disjunctor, through a study using finite elements (FE). The results demonstrate that the custom device developed by Battistetti transmits the force much more efficiently compared to Hyrax, and there is no dental commitment. It is also observed a bigger bone displacement using bone-borne device in addition to a smaller disjunctor fatigue.