Contact angle measurement on dental implant biomaterials.

Wettability may be one of the surface factors to be considered when selecting dental implant biomaterials. Contact angles of dental implant surface preparations influence wettability and tissue adhesion. The contact angles of eight implant surface preparations were determined in this study. Contact angles were measured by a tele-microscope equipped with a protractor eyepiece. Groups 1 to 6 had a Ti6Al4V substrate. Group 1 was metallurgically polished, group 2 was blasted with 180 microns Al2O3, group 3 was blasted with 710 microns Al2O3, group 4 was hydroxyapatite (HA) blasted (125 microns), group 5 had a Calcitite HA plasma-sprayed coating, and group 6 was coated with plasma-sprayed MP-1 HA. Group 7 was metallurgically polished commercially pure (CP) titanium (grade 1), and group 8 was etched CP titanium (grade 1). Contact angles were measured 30 times for each group with distilled water and glycerol, and the determinations were statistically analyzed. Mean contact angles for groups 1 to 8 were 65.5, 65.3, 62.5, 67.9, 46.6, 81.7, 58.5, and 69.0, respectively, when tested with distilled water, and 70.7, 68.3, 81.6, 75.4, 67.1, 70.7, 62.3, and 82.5, respectively, when tested with glycerol. Analysis of variance and Tukey's Honestly Significant Difference test (p = 0.05) demonstrated significant differences between group 5 and all other groups when groups were tested with distilled water and demonstrated no significant differences between groups 5 and 7 when groups were tested with glycerol. Surface preparation of implant biomaterials affects wettability. In this study, Ti6Al4V coated with Calcitite HA had the lowest contact angles and the best wettability.