Surface and Biocompatibility Outcomes of Chemical Decontamination in Peri-Implantitis Management

<b>Background and Objectives:</b> Peri-implantitis is a biologically driven complication that jeopardizes dental implant longevity. While chemical decontamination is frequently employed as an adjunct to mechanical debridement, its impact on implant surface integrity and cellular compatibility remains insufficiently defined. This study aimed to evaluate the effects of several chemical agents used in peri-implantitis treatment on the surface morphology and potential biocompatibility of titanium dental implants. <b>Materials and Methods:</b> Twenty-five Ti6Al4V implants were exposed to one of the following agents: saline solution, 3% hydrogen peroxide, 40% citric acid, 17% EDTA, and a mixture (1:1) of citric (2%) and phosphoric (1N) acids. This in vitro study employed a 7-day immersion protocol to accentuate surface effects under controlled laboratory conditions, acknowledging that clinical exposures are substantially shorter. Surface topography was evaluated by Atomic Force Microscopy, while cellular response and corrosion products were assessed using Scanning Electron Microscopy. Surface roughness parameters were statistically analyzed. <b>Results:</b> Hydrogen peroxide induced selective corrosion of the β phase and formed a compact passivation layer that supported mesenchymal stem cell adhesion. Citric acid etched grain boundaries, producing localized roughness that also permitted cell proliferation. EDTA caused advanced grain dissolution and debris accumulation, increasing surface roughness but impairing cellular adhesion. The citric-phosphoric acid mixture led to the highest roughness values and visible corrosion debris. In all cases, macrostructural integrity of the implants was preserved. <b>Conclusions:</b> Chemical agents used in peri-implantitis treatment induce distinct surface alterations on titanium implants. Controlled use of hydrogen peroxide and citric acid may enhance surface biocompatibility, while aggressive protocols such as EDTA and acid combinations require caution due to their adverse effects on surface morphology and cellular response. These findings may inform the development of optimized decontamination protocols for clinical management of peri-implantitis.