Análise por elementos finitos de nova proposta de dispositivo para redução e fixação das fraturas de côndilo mandibular

Abstract

The large incidence and the controversies related to the diagnose, forms of treatment, surgical accesses and osteosynthesis material types, determine that condylar fractures have a featured place among facial fractures. It is possible to perform a surgical or non surgical treatment depending on the endless situations and clinical indications. After choosing the surgical access, one should obtain an adequate reduction of the fractures and an effective internal fixation, respecting the anatomic characteristics of the condylar region, in order to obtain a satisfying funcional result. Plates configurations, isolated or not, with different shapes and sizes, can be used for a surgical solution to the condylar fractures. Aiming an enhancement of the advantages and decreasing of the disadvantages, regarding the fixation techniques, the screw Neck Screw was developed, with the purpose of creating the stabilization required to achieve a correct fixation through a dynamic compression system, increasing the contact between the fractured bone stubs, as well as serving as an ally when reducing the fractures. The present paper has as objective to evaluate the fixation and the stability of the jaw condyle fractures, and compare four fixation techniques: the first configuration presents a 2.0 mm plate, with four holes in it, the second one has two plates, one of 2.0 mm and the other with 1.5 mm, both with four holes in it and screws 6.0 mm long, the third fixation system has the Neck Screw and a “L” shaped plate, with four holes, 2.0 mm wide, overlapped between them, and the last one has the Neck Screw and the “L” shaped plate forming a single device, united through a solder. The results demonstrate a better stability when using two plates, regarding the dislocation of the fractures, synthesis materials deformation, minimal and maximal tension values. The results with the Neck Screw are satisfying, much as the ones found when using a mini plate, being, therefore, an alternative to the reduction and fixation of condylar fractures, if correctly indicated and with an adequate surgical sequence and technique.