Confecção e avaliação mecânica de implantes ortopédicos produzidos em poli (L-ácido lático) (PLLA) por impressoras 3D

Abstract

The objective of this work the production and biomechanical evaluation of structural orthopedic implants for fracture fixation in bioresorbable polymer, poly (lactide L) (PLLA) using a printing technique 3D deposition of layers of polymer melt for further experimental application in femur rabbit. For the production of implants, i.e. orthopedic plates curved section and locking screws it was taken as base femurs anatomy rabbits slaughtered for consumption which have had their dimensions and measured shapes as a reference for computer aided design (CAD) in specific program. The project was suitable for a three-dimensional modeling program controller of a printer in 3 dimensions printed, by deposition of layers, plates and orthopedic screws. The models were subjected to mechanical strength tests, three models of plates 4 and 6 holes with locking screw, and a plate anatomically optimized addition of a suitable screw type blocked plates. In the bending strength test with 4 points of support for 6 holes plate obtained values of 748 ± 62 N while the blocked plate 4 holes obtained values of 374 ± 42 N. The screw was subjected to peel strength testing in a polyurethane foam which simulates the cortical bone, the average value was 33 ± 6 N. the optimized anatomically plate obtained in the bending test after 662 ± 220N and irradiated with 40 kGy 193 ± 20N. From the point of view of mechanical resistance to bending test work showed the viability of producing structural orthopedic implants for fracture receiving little mechanical load although necessary in vivo tests that prove the effectiveness of the production technique and the material used.