Effect of chemical and mechanical debridement techniques on bacterial re-growth on rough titanium surfaces: an in vitro study

Objective: The aim of this in vitro study was to compare the effect of combined chemical and mechanical debridement of titanium (Ti) surfaces inoculated with Staphylococcus epidermidis, compared with the effect of chemical debridement alone.

Material and methods: Different Ti surfaces were characterized with respect to roughness and subsequently inoculated with S. epidermidis. NaCl (0.9 vol.%), EDTA (12 vol.%), H₂O₂ (3 vol.%) or H₂O₂ + TiO₂ nanoparticles served as chemical debridement agents, while TiBrush was used as the mechanical debridement tool. Safranin staining assessed biomass still attached to surfaces after debridement. Biofilm viability was assessed after re-incubation of the debrided samples. SEM analysis was performed before and after the cleaning process.

Results: Surface average roughness (Sa ) of the samples was measured at 2.22 ± 0.19 μm for group A, 0.19 ± 0.02 μm for group B, and 1.99 ± 0.10 μm for group C. When chemical debridement agents were used alone, H₂O₂-containing products were most efficient in reducing the biomass load. The surface roughness did not affect the outcome of chemical debridement. However, when combining chemical and mechanical debridement, a further reduction of biofilm load and viability was observed with best effect on the smoothest surface.

Conclusions: Combining H₂O₂-containing chemical agents with mechanical debridement (TiBrush) provided best reduction in biofilm mass and re-growth, when studied in vitro.