Effect of anodized titanium abutment collars on peri-implant soft tissue: A split-mouth clinical study

Statement of problem Anodic oxidation of titanium implant abutment collars has been used to mask their unesthetic grayish color. However, the effect of anodic oxidation on the health and appearance of peri-implant soft tissues is unclear. Purpose The purpose of this split-mouth clinical study was to investigate the effect of anodized titanium on the health and esthetics of peri-implant soft tissues. Material and methods A total of 60 osseointegrated implants placed in 30 participants were included in the present study. Each participant received 2 randomly allocated abutments, one with a pink anodized collar and the other with an unanodized one to form 2 groups: unanodized group (control group) and anodized group (experimental group). All implants were restored with lithium disilicate restorations. Evaluations of the peri-implant soft tissues were performed at the time of definitive restoration insertion (baseline) and after 3, 6, 12, and 18 months: peri-implant probing depth, soft tissue recession, modified sulcus bleeding index, modified plaque index, and modified gingival index. The esthetics of peri-implant soft tissues were evaluated by using the modified pink esthetic score. The paired t test or Wilcoxon signed-rank test was used for comparing the 2 study groups at each point of time depending on the normality of the variables (α=.05). To compare each variable at different time points within each group separately, repeated measures ANOVA or Friedman tests were used according to the normality of the variables, followed by post hoc pairwise comparisons by using the Bonferroni adjusted significance (α=.05). Results Five peri-implant soft tissue indices were followed up throughout the study. No statistically significant differences were found among the mean values of the tested indices in the anodized and unanodized groups throughout the evaluation periods (P>.05). The collective mean values of the modified pink esthetic score also showed no statistically significant differences between the groups (P>.05). Conclusions Based on this split-mouth clinical study, pink anodized titanium abutment collars do not produce a clinically significant effect on the health or esthetics of peri-implant soft tissues.