Effectiveness and Surface Changes of Different Decontamination Protocols at Smooth and Minimally Rough Titanium Surfaces.

BACKGROUND:The objective of this study is to evaluate titanium decontamination after different protocols while assessing changes in surface roughness, chemical composition, and wettability. METHODS:Ninety-six smooth (S) and 96 minimally rough (R) titanium microimplants were used. Pristine microimplants were reserved for negative control (S-nC/R-nC, n = 9), while the remaining microimplants were incubated in Escherichia coli culture. Non-decontaminated microimplants were used as positive control (S-pC/R-pC, n = 3). The other microimplants were divided into seven different decontamination protocols (12 S/R per group): 24% EDTA, 2% chlorhexidine (CHL), gauze soaked in 2% chlorhexidine (GCHL), gauze soaked in ultrapure water (GMQ), scaling (SC), titanium brush (TiB), and implantoplasty (IP). Contaminated areas were assessed by scanning electron microscope images, chemical composition by energy dispersive X-ray spectroscopy, wettability by meniscus technique, and roughness by an optical profiler. RESULTS:Higher residual bacteria were observed in R-pC compared with S-pC (P <0.0001). When comparing S and R with their respective pC groups, the best results were obtained with GCHL, SC, TiB, and IP, with no difference between these protocols (P >0.05). Changes in surface roughness were observed after all treatments, with S/R-IP presenting the smoother and a less hydrophilic surface (P <0.05). Apart from IP protocol, all the other groups presented a more hydrophilic surface in R than in S microimplants (P <0.003). All decontamination protocols resulted in a lower percentage of superficial Ti when compared with S/R-nC (P <0.002). CONCLUSIONS:All decontamination protocols resulted in changes in roughness, wettability, and chemical composition, but GCHL, SC, TiB, an IP presented the best decontamination outcomes.