A Systematic Review of the 5-year Survival and Complication Rates of Implant-Supported Single Crowns

Clin Oral Implants Res. 2008 Feb;19(2):119-30. doi: 10.1111/j.1600-0501.2007.01453.x. Epub 2007 Dec 7.


Objectives: The objective of this systematic review was to assess the 5-year survival of implant-supported single crowns (SCs) and to describe the incidence of biological and technical complications.

Methods: An electronic MEDLINE search complemented by manual searching was conducted to identify prospective and retrospective cohort studies on SCs with a mean follow-up time of at least 5 years. Failure and complication rates were analyzed using random-effects Poisson's regression models to obtain summary estimates of 5-year proportions.

Results: Twenty-six studies from an initial yield of 3601 titles were finally selected and data were extracted. In a meta-analysis of these studies, survival of implants supporting SCs was 96.8% [95% confidence interval (CI): 95.9-97.6%] after 5 years. The survival rate of SCs supported by implants was 94.5% (95% CI: 92.5-95.9%) after 5 years of function. The survival rate of metal-ceramic crowns, 95.4% (95% CI: 93.6-96.7%), was significantly (P=0.005) higher than the survival rate, 91.2% (95% CI: 86.8-94.2%), of all-ceramic crowns. Peri-implantitis and soft tissue complications occurred adjacent to 9.7% of the SCs and 6.3% of the implants had bone loss exceeding 2 mm over the 5-year observation period. The cumulative incidence of implant fractures after 5 years was 0.14%. After 5 years, the cumulative incidence of screw or abutment loosening was 12.7% and 0.35% for screw or abutment fracture. For supra-structure-related complications, the cumulative incidence of ceramic or veneer fractures was 4.5%.

Conclusion: It can be concluded that after an observation period of 5 years, high survival rates for implants and implant-supported SCs can be expected. However, biological and particularly technical complications are frequent.

Publication types

  • Meta-Analysis
  • Review
  • Systematic Review

MeSH terms

  • Crowns / statistics & numerical data
  • Dental Implantation, Endosseous / adverse effects
  • Dental Implantation, Endosseous / statistics & numerical data*
  • Dental Implants, Single-Tooth / adverse effects
  • Dental Implants, Single-Tooth / statistics & numerical data*
  • Dental Restoration Failure*
  • Humans
  • Periapical Periodontitis / diagnostic imaging
  • Periapical Periodontitis / epidemiology
  • Periapical Periodontitis / etiology
  • Poisson Distribution
  • Radiography
  • Survival Analysis