This work reports on the surface characterisation of Bis-GMA/TEGDMA biocompatible resins after high energy He+ or N2+ ion implantation treatments. The samples have been characterised by diffusive reflectance FT-IR, X-ray phoelectron spectroscopy, ultramicro-hardness and nano-scratch wear tests. In addition, osteblast cell assays MG-63 have been used to test the biocompatibility of the resin surface after the ion implantation treatments.

The chemical modification induced on the resin surfaces by the interaction of the accelerated ions have been correlated to the mechanical and wear properties of the exposed surfaces, as a function of the energy and dose of the impinging species. It has been observed that the maximum surface hardening of the resin surfaces is achieved at He-ion implantation energies of around 50 keV, and doses of 1x1016 cm-2. At 50 keV of He-ion bombardment, the wear rate of the resin surface decreases by a factor 2 with respect to the pristine resin. All these results evidence that ion implantation is an effective technique to produce a significant hardening on UV-cured resins. Whereas ion implantation has been extensively proved in thermoplastics such as PET, PC’s or PE, few research works have investigated its effects on thermosets. Finally, in-vitro tests indicate that the He-ion implantation does not much affect the cell-proliferation behavior of the pristine UV-cured resin.

The enhancement of the surface mechanical properties of these materials can have beneficial consequences, for instance in preventing wear and surface fatigue of bone-fixation prostheses, whose surfaces are continuously held to sliding contacts of sub-millimetre amplitude.