Five-year outcomes of a randomized controlled clinical trial comparing single-tooth implant-supported restoration with either zirconia or titanium abutments.

Abstract

To evaluate the influence of the abutment material (zirconia vs. titanium) on the long-term aesthetic and clinical outcomes of implant-supported restorations. In 30 patients, a single implant-supported restoration with either a zirconia or a titanium abutment was placed in the anterior maxilla (incisors, canines, and bicuspids). Aesthetic (Implant Crown Aesthetic Index or ICAI), clinical, radiographic, and patient-centred outcomes were recorded at baseline (1 month after final restoration), 1year, and 5 years of follow-up. This study was registered in ClinicalTrials.gov (NCT02315794). Twenty-five subjects completed the follow-up visits at 1 and 5 years. ICAI values showed statistically significant better aesthetic outcomes when zirconia abutments were used compared to titanium abutments. Between 1 and 5 years, the aesthetic sub-analysis of the crown component worsened but the mucosal sub-analysis improved. There were no significant changes in bone levels, but the plaque index, bleeding on probing, and probing depths worsened in both groups. At 5 years, standard zirconia abutments achieved better aesthetic outcomes, although with similar clinical behaviour.