Detoxification of Titanium Implant Surfaces: Evaluation of Surface Morphology and Bone-Forming Cell Compatibility

Abstract

Peri-implantitis is one of the major clinical conditions associated with dental implant failure. Adhesion of bacterial biofilm is considered as the primary etiological factor for this condition. A commonly used therapeutic method for surgical removal of adhered biofilm is mechanical debridement, which may cause detrimental effects on the implant surface. Post-treatment, implants are expected to re-osseointegrate with bone tissue, providing mechanical stability. However, it is important to understand that both bacterial adhesion and detoxification procedures can affect the titanium surface, which is vital for growth of bone-forming cells, osteoblasts. The goal of this study was to evaluate the synergistic effect of bacterial adhesion and detoxification treatment method on subsequent bone cell growth on implant surface. Polished titanium specimens underwent bacterial contamination and debridement/detoxification treatment with acidic and neutral chemicals to model a treatment for a peri-implantitis-infected dental implant. Subsequently, bone cell activity and surface morphology were evaluated using standard cell viability/differentiation assays, scanning electron and optical microscopies, respectively. The synergistic activity of bacterial contamination and detoxification with acidic chemicals generally lowered cell viability and proliferation rates. This suggested higher toxicity of titanium surfaces imparted by detoxification methods on osteoblasts. Electrochemical testing corroborated visual signs of corrosion attack and revealed that immersion-treated specimens had higher corrosion resistance than their corresponding rubbing-treated counterparts, excluding saline. Overall, surface damage induced by detoxification methods must be considered when selecting the most appropriate therapy to increase the probability of re-osseointegration of titanium substrates.