Relationship Between Roughness and Wettability of Nine Types of Implant Surfaces and Potential Interference of Surface Oxygen and Carbon: In Vitro Evaluation.

Purpose: To assess the roughness and hydrophilicity of nine types of dental implant surfaces, examine the presence of contaminants-such as carbon and oxygen-on these surfaces, and explore potential correlations among these characteristics across the analyzed surfaces.

Materials and methods: The analyzed surfaces were as follows: machined (turned) (MI) (Implacil De Bortoli), blasted with titanium (Ti) oxide (TOI) (Implacil De Bortoli), blasted with Ti oxide and acid etched (TOAEI) (Implacil De Bortoli), blasted with zirconia (Zr) and acid etched (ZAED) (DSP Medical), coated with calcium phosphate (CPD) (DSP Medical), subjected to an experimental treatment (patent pending; XD) (DSP Medical), double acid etched and activated with hydroxyapatite nanocrystals (DAEHAS) (S.I.N.), double acid etched (DAES) (S.I.N.), and untreated surface of the Plenum implant (AMP) produced by additive manufacturing (Plenum). Four disc-shaped specimens of each surface type were used in the hydrophilicity analyses, and five disc-shaped specimens of each surface type were used in the roughness analyses. Roughness was evaluated by optical profilometry and scanning electron microscopy, hydrophilicity was determined using the sessile-drop technique, and the chemical analysis was performed using X-ray photoelectron spectroscopy (XPS). The Kruskal-Wallis, Mann-Whitney U, and Spearman correlation tests were employed to analyze the data (P < .10).

Results: Significant differences were observed among the analyzed surfaces in terms of both roughness and hydrophilicity (P < .001). The surface that exhibited the highest roughness was AMP, whereas the greatest hydrophilicity was exhibited by the CPD surface. Correlations between roughness and hydrophobicity were only observed for the MI surface (r = 0.936, P = .009), ZAED surface (r = 0.957, P = .004), and DAES surface (r = 0.964, P = .005). The carbon concentration observed on the CPD surface was lower than that observed on the other surfaces, whereas the oxygen concentrations were similar across all groups. No correlations were observed between the presence of contaminants and the roughness or hydrophilicity characteristics.

Conclusions: The roughness and hydrophilicity values exhibited considerable variation among the tested surfaces. Aside from the CPD surface, comparable concentrations of carbon and oxygen were detected. Although correlations between roughness and hydrophilicity were observed only for the ZAED, DAES, and MI surfaces, these correlations were inadequate to establish a causal relationship between the two surface characteristics.