Adverse effects of sterilization processes on the fundamental topographic properties of modified dental implant surfaces

The employ of sterilization processes are essential to investigate biomaterials aiming for experimental, preclinical, or clinical applications with biological tissues. However, responsive surface properties of biomaterials may be susceptible to sterilization processes, compromising important physio-chemical characteristics. For that reason, this in vitro study aimed to investigate the effects of three different processes for sterilization (humid heat under pressure, UVC-light exposure, and Gamma irradiation) on the major topographical properties of implant surfaces applied to dental bone-anchored implants and/or implant-abutments. Three groups of implant surfaces were developed: a smooth machined surface, a micro-texturized surface, and a hydrophilic micro-texturized surface. The implants were sterilized with three methodologies and characterized regarding surface morphology, elemental surface composition, roughness parameters, wettability characteristics, and compared to the samples as-developed. Surface morphology and roughness parameters were not modified by any of the sterilization processes applied. On the other hand, hydrophilic implants were negatively affected by autoclaving. After package opening, hydrophilic features showed to be sensible to atmospheric air exposition independently of the sterilization process performed. Our findings revealed significant chemical changes on the implant surfaces caused by autoclaving and UVC exposure; additionally, the results showed the importance of selecting an appropriate sterilization method when investigating hydrophilic implants so as not to generate imprecise outcomes.

Graphical Abstract