Clinical Evaluation of Single Implants Restored with Nitride-treated Titanium Abutments

Objectives: To enhance gingival esthetics of implant-supported restorations, gold-colored nitride-treated titanium (TiN) abutments have been introduced. The purpose of this study was to evaluate the esthetics and functional stability of zirconia-based implant-supported restorations with custom TiN abutments in the premolar region.
Methods: 20 participants requiring single maxillary premolar implants were selected for this study after meeting inclusion criteria. Nine months after surgical implant placement, implants were restored with TiN abutments (BellaTek,3i) and minimally veneered zirconia crowns (Lava,3M). Subjects were evaluated at 2 weeks and at 6, 12, and 24 months after restoration placement. Clinical parameters of mechanical stability and soft tissue health/esthetics as well as patient satisfaction were evaluated. A non-parametric Friedman test was used to statistically analyze the data.
Results: No complications in terms of abutment fracture or screw loosening were observed for all 20 abutments. Clinical survival rate was 100% during the 24-month follow-up period. Mean soft tissue recession was 0.27mm in mesial papilla, 0.33mm in distal papilla and 0.07mm in facial gingival margin. The mean index score of soft tissue color changes in relation to the adjacent teeth was 0.13 and ranged from 0 (indistinguishable) to 1.0 (barely distinguishable). No significant differences were observed in terms of soft tissue recession and soft tissue color change among restorations at 2 week, 6 month, 12 month, and 24 month follow-ups (p>0.05). Mean patient satisfaction was 9.4 (0-10 scale) and no signs of severe inflammation were recorded at any of the abutments during the 24-month follow-up period. The mean gingival index score at 6- month follow-up (0.88) was significantly higher (p<0.05) when compared to that at 2 week- (0.31), 12 month- (0.25) and 24 month- (0.5) follow-ups.
Conclusions: Zirconia-based implant-supported restorations with custom TiN-coating abutments demonstrated promising functional stability and soft tissue health/esthetics throughout the 2-year follow-up period.