Cemented versus screw‐retained zirconia‐based single‐implant restorations: 5‐year results of a randomized controlled clinical trial. Issue 4 (2nd February 2022)

• Record Type: Journal Article
• Authors: Lamperti, Sofia T.; Wolleb, Karin; Hämmerle, Christoph H.F.; Jung, Ronald E.; Hüsler, Jürg; Thoma, Daniel S.
• Is Part Of: Clinical oral implants research. Volume 33:Issue 4(2022)
• Page Start: 353
• Page End: 361
• Publication Date: 2022-02-02
• Subjects: cemented -- crowns -- dental abutments -- screw‐retained -- single‐tooth dental implants; Dental implants -- Research -- Periodicals; 617.69
• DOI: 10.1111/clr.13895
• Languages: English
• ISSNs: 0905-7161

Abstract

Abstract: Objectives: To compare cemented and screw‐retained one‐piece zirconia‐based restorations in terms of clinical, radiographic, and technical outcomes 5 years after insertion. Materials and methods: Thirty‐four patients with single‐tooth implants were randomly restored with either a cemented lithium disilicate crown on a one‐piece customized zirconia abutment (CEM, 17 patients) or a screw‐retained crown based on a directly veneered one‐piece customized zirconia abutment (SCREW, 16 patients). All patients were recalled for a baseline examination (7–10 days after crown insertion) and then annually up to 5 years. The following outcomes were assessed: marginal bone level (changes), technical, and clinical (bleeding on probing, plaque control record, probing depth, and keratinized tissue) parameters. The Mann – Whitney U ‐test was used to assess differences between the two groups. Results: At 5 years, 26 patients (13 in each group) were re‐examined. The survival rates on the implant and restorative levels were 100% and 82.4% (equally for both groups), respectively. At 5 years, the median marginal bone level was located at −0.15 mm (IQR: −0.89 mm; 0.27 mm) (CEM) and −0.26 mm (IQR: −0.38 mm; 0.01 mm) (SCREW) below the implant shoulder (intergroup p = .9598). The median changes between baseline and the 5‐year follow‐up amounted to −0.23 mm (CEM; intragroup p = .0002) and −0.15 mm (SCREW; intragroup p = .1465) (intergroup p = .1690). The overall technical complication rate at 5 years was 15.4% (CEM) and 15.4% (SCREW) (intergroup p = 1.00). Clinical parameters remained stable over time (baseline to 5 years). Conclusions: At 5 years, screw‐retained and cemented restorations rendered largely the same clinical, technical, and radiographic outcomes. Technical complications were frequent in both groups.