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Randomized Controlled Trial
. 2022 May;33(5):537-547.
doi: 10.1111/clr.13913. Epub 2022 Mar 3.

Five-year randomized controlled clinical study comparing cemented and screw-retained zirconia-based implant-supported single crowns

Riccardo D Kraus  1 , Catharina Espuelas  1 , Christoph H F Hämmerle  1 , Ronald E Jung  1 , Irena Sailer  2 , Daniel S Thoma  1
Affiliations
Randomized Controlled Trial

Five-year randomized controlled clinical study comparing cemented and screw-retained zirconia-based implant-supported single crowns

Riccardo D Kraus et al. Clin Oral Implants Res. 2022 May.

Abstract

Objectives: To compare screw-retained and cemented all-ceramic implant-supported single crowns regarding biological and technical outcomes over a 5-year observation period.

Materials and methods: In 44 patients, 44 two-piece dental implants were placed in single-tooth gaps in the esthetic zone. Patients randomly received a screw-retained (SR) or cemented (CR) all-ceramic single crown and were then re-examined annually up to 5 years. Outcome measures included: clinical, biological, technical, and radiographic parameters. Data were statistically analyzed with Wilcoxon-Mann-Whitney, Wilcoxon, and Fisher's exact tests.

Results: During the observation period, three patients (6.8%) were loss to follow-up. Eight restorations (18.2%, CI (8.2%, 32.7%)) were lost due to technical (6 patients, 13.6% (CI (5.2%, 27.4%)), 2 CR and 4 SR group, intergroup p = .673; implants still present) or biological complications (2 patients, 4.5% (CI (0.6%, 16.5%)), only CR group, intergroup p = .201, both implants lost). This resulted in a survival rate of 81.2% (CI (65.9%, 90.1%)) on the restorative level (18 SR; 15 CR, 3 lost to follow-up). At the 5-year follow-up, the median marginal bone levels were located slightly apical relative to the implant shoulder with 0.4 mm (0.5; 0.3) (SR) and 0.4 mm (0.8; 0.3) (CR) (intergroup p = .582). Cemented restorations demonstrated a significantly higher biological complication rate (36.8%, SR: 0.0%; intergroup p = .0022), as well as a significantly higher overall complication rate (68.4%, SR: 22.7%, intergroup p = .0049). All other outcomes did not differ significantly between the two groups (p > .05).

Conclusions: All-ceramic single-tooth restorations on two-piece dental implants resulted in a relatively low survival rate. Cemented restorations were associated with a higher biological and overall complication rate than screw-retained restorations.

Keywords: biologic complications; cemented; ceramic abutments; implant abutments; screw-retained; single crowns; technical complications; zirconia.

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Conflict of interest statement

The authors report no conflict of interest.

Figures

FIGURE 1
FIGURE 1
All‐ceramic implant‐borne screw‐retained restoration at baseline (a) and at 5‐year follow‐up (b). Site 12
FIGURE 2
FIGURE 2
All‐ceramic implant‐borne cemented restoration at baseline (a) and at 5‐year follow‐up (b). Site 24
FIGURE 3
FIGURE 3
Kaplan–Meier plot with 95% confidence limits
See this image and copyright information in PMC

References

    1. Agar, J. R. , Cameron, S. M. , Hughbanks, J. C. , & Parker, M. H. (1997). Cement removal from restorations luted to titanium abutments with simulated subgingival margins. Journal of Prosthetic Dentistry, 78(1), 43–47. 10.1016/S0022-3913(97)70086-6 - DOI - PubMed
    1. Ainamo, J. , & Bay, I. (1975). Problems and proposals for recording gingivitis and plaque. The International Dental Journal, 25, 229–235. - PubMed
    1. Amorfini, L. , Storelli, S. , Mosca, D. , Scanferla, M. , & Romeo, E. (2018). Comparison of cemented vs screw‐retained, customized computer‐aided design/computer‐assisted manufacture zirconia abutments for esthetically located single‐tooth implants: A 10‐year randomized prospective study. The International Journal of Prosthodontics, 31(4), 359–366. 10.11607/ijp.5305 - DOI - PubMed
    1. Bidra, A. S. , & Rungruanganunt, P. (2013). Clinical outcomes of implant abutments in the anterior region: A systematic review. Journal of Esthetic and Restorative Dentistry, 25(3), 159–176. 10.1111/jerd.12031 - DOI - PubMed
    1. Cvar, J. F. , & Ryge, G. (2005). Reprint of criteria for the clinical evaluation of dental restorative materials. Clinical Oral Investigations, 9(4), 215–232. 10.1007/s00784-005-0018-z - DOI - PubMed

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