In vitro comparison of commercial and ultrafine-grained titanium osteosynthesis miniplates used on mandibular fractures.

BACKGROUND

Implants called miniplates, with different geometries, are used for the treatment of a fractured or diseased mandible. Generally, Ti-based miniplates in various quantities and with various geometries are fixed into the bone tissue according to the location and shape of the fracture by embedding.

OBJECTIVES

The aim of this study was to increase the strength of the material used in the production of miniplates by means of the equal-channel angular pressing (ECAP) treatment, and to provide a highrigidity fixation system with fewer miniplates.

MATERIAL AND

METHODS

In this study, the ECAP method, which is one of the methods of severe plastic deformation, was applied at 4 passes at 300°C in route Bc to increase the strength of pure Ti. Then, miniplates were produced with 2 different geometries (regular and long) and 2 different properties of the Ti material (untreated and ECAP-treated). The produced miniplates were placed in the fracture line formed in the angular region of an artificial, synthetic-bone mandible. The 2-point and 3-point bending and torsion tests were conducted on these fixation systems.

RESULTS

As a result, after the ECAP process, the yield and tensile strength of pure Ti increased by 65%, while elongation decreased by 13%. After the ECAP process, the grain size of the material was reduced from 110 μm to 200 nm.

CONCLUSIONS

This study showed that the fixation system became more rigid due to using ECAP-treated miniplates, and this ensured lesser displacement of the fixation system.