Metodologia de ensaio para análise de desgaste em próteses de articulação temporomandibular

AUTOR(ES)
DATA DE PUBLICAÇÃO

2006

RESUMO

Patients who had suffered some kind of trauma or pathogenic disease which involves the temporomandibular joint (TMJ), where the bone reposition is not applicable may have the joint replaced by a prostheses. Different kinds of prostheses have been proposed, some of them with success. The present work has, as main objective, to develop a specific methodology to evaluate the wear behavior of TMJ prostheses. It was, therefore, created an in vitro methodology which reproduces the characteristics in vivo, regarding the movements and dimensions of the implanted TMJ prostheses. In order to reach the considered objective, was projected and assembled a specific equipment for the test. The equipment was developed in order to reproduce parameters in vivo of the TMJ prostheses users such as buccal opening with condilar rotational movement of 28 and frequency of 2 Hz, data extracted from clinical literature. A force of 200 N was applied during 7 million of cycles, which correspond to 10 years of use of the prostheses. As lubricant, bovine fetal serum was used with antibiotic and EDTA added to it. The materials selected for this study were the most common that have been used in this type of prostheses, which is, pin made on Chromium-Cobalt-Molybdenium alloy (CoCrMo) sliding against ultra high molecular polyethylene (UHMWPE). The samples were weighted at each 1,4 million of cycles and it was calculated the wear rates form the first to the fifth weight measurement. The result of the test showed characteristics of adhesion wear followed by three body wear, which is a typical behavior found during sliding of pairs of materials having different hardness. It was concluded that the methodology of the in vitro test proposed simulated the in vivo characteristics of an implanted TMJ prostheses and the equipment constructed represented the methodology proposed. The wear tests for total hip replacement (THR) prostheses present different results from that found during the test proposed in this work for specific analysis of TMJ prostheses.

ASSUNTO(S)

engenharia medica desgaste mecânico engenharia biomédica prótese maxilo-facial articulação temporomandibular

Documentos Relacionados