Chemical debridement of contaminated titanium surfaces: Anin vitrostudy

OBJECTIVE: To compare the efficacy of different chemical solutions when used for chemical debridement of biofilm contaminated titanium surfaces in an in-vitro experimental study. MATERIALS AND METHODS: Commercially pure titanium discs with a diameter of 6.2 mm and height of 2 mm, mirror-polished with a measured surface amplitude value SA = 0.037 μm ± 0.009 were used as test-surfaces. A biofilm was simulated with multi-layers of Staphylococcus epidermidis ATCC359844 covering the entire titanium surface. The chemical agents tested were: 3% H2O2, 0.2% Chlorhexidine, 24% EDTA-gel, 3% H2O2 mixed with 1.6 g/L TiO2 and sterile saline solution. The decontamination effect was evaluated by optical density analysis using spectrophotometry and with scanning electron microscopy (SEM) images of the remaining biofilm. RESULTS: The suspensions of 3% H2O2 and 1.6 g/L TiO2 or 3% H2O2 alone were the most effective in removing S. epidermidis biofilms (p < 0.05), whereas 0.2% chlorhexidine or 24% EDTA gel had no significant effects. SEM images of the remaining biofilms supported the quantitative results indicating the higher efficacy of 3% H2O2 and 1.6 g/L TiO2 or 3% H2O2 alone. It also revealed that EDTA, despite a non-significant effect on reducing the amount of established biofilms, was able to alter the biofilm architecture, as demonstrated by increased interspaced regions. CONCLUSIONS: In this in vitro study the decontamination potential of a suspension of 3% H2O2 and 1.6 g/L TiO2 or 3% H2O2 alone were encouraging. Whether such procedures would have a similar effect in vivo remains to be determined.