Narrow Versus Standard Diameter Implants for Supporting Single Crown Restorations in the Posterior Jaw: A Randomised Controlled Trial.

Abstract

Objectives: The aim of this randomised controlled trial was to assess clinical, radiographic and patient reported outcomes of narrow versus standard diameter titanium zirconium (TiZr) implants supporting single crown restorations in posterior sites with limited bone width.

Materials and Methods: Participants requiring replacement of single missing posterior teeth with implant-supported crowns were randomly allocated into 2 treatment groups: narrow (3.3 mm) or standard (4.1 mm) diameter implant. All implants were restored with screw-retained monolithic zirconia crowns. The changes in marginal bone level (MBL) were assessed at the time of delivery of definitive crown and after 1 year of function. Implant stability was measured at placement, 3 and 12 months. Implant success, pink esthetic score (PES), peri-implant parameters, and patient satisfaction were also evaluated.

Results: A total of 20 participants with 20 implant-supported single crowns completed the 1-year follow-up. All implants were successful. The narrow diameter implants had a higher bone remodeling of 0.39 ± 0.92 mm after 1 year of loading compared with only 0.10 ± 0.29 mm for the standard diameter implants but the difference was not statistically significant (P = .40). There were no statistically significant differences between the 2 implant groups in terms of PES and peri-implant outcomes.

Conclusions: Narrow and standard-diameter TiZr implants supporting screw-retained monolithic zirconia crowns in the posterior region were reliable treatment modalities with comparable clinical, radiographic and patient reported outcomes after 1 year of function. Patient satisfaction was high in both treatment groups.