Abstract
Background: The aim of this study was to compare the one-year clinical outcomes and patient satisfaction scores of replacing a single missing posterior tooth using either narrow- or regular-diameter tissue-level titanium-zirconium (TiZr) implants (NDI, RDI respectively) with screw-retained monolithic zirconia crowns.
Materials and Methods: Thirty-nine patients with 43 implants were included and randomly assigned into two groups: Group 1 received NDI (3.3 mm); Group 2 RDI (4.1 mm). All implants were conventionally loaded at 3 months with screw-retained monolithic zirconia crowns. Implant and prosthodontic success/survival rates were measured based on changes in marginal bone level, implant stability (ISQ), prosthetic outcomes and peri-implant parameters. Additional information such as volumetric change, pink esthetic outcomes (PES), and oral health related quality of life (OHRQoL) were assessed at the crown delivery (baseline) and at the one-year follow-up.
Results: A total of 36 participants with 39 single implant crowns completed the one-year follow-up. Three patients with four NDIs were lost to follow-up. Both the NDI and RDI group had an implant and prosthetic survival rate of 100%. No significant differences were found in terms of prosthetic outcomes, soft tissue outcomes, esthetic outcomes and patient satisfaction. The NDI group had a mean marginal bone loss of 0.20 ± 0.67mm, while the RDI group had less mean bone loss of 0.05 ± 0.35mm; however, this difference was not statistically signiQicant (p = 0.15). ISQ values for NDI group were significantly lower than RDI at baseline (70.0 ± 9.3 and 75.0 ± 5.3 respectively, p = 0.04) and at one-year follow up (75.6 ± 7.8 and 81.5 ± 6.0 respectively, p = 0.02). Oral health related quality of life (OHRQoL) measured using the general oral health assessment index (GOHAI) increased signiQicantly (p = 0.00) for both groups from low to moderate.
Conclusion: NDI and SDI TiZr implants supporting single monolithic zirconia crowns in the posterior regions were reliable treatment modalities with comparable clinical, radiographic and patient reported outcomes after one year of function.