The impact of cantilevers on biological and technical success outcomes of implant-supported fixed partial dentures. A retrospective cohort study

Clin Oral Implants Res. 2014 Feb;25(2):175-84. doi: 10.1111/clr.12102. Epub 2013 Jan 2.

Abstract

Objective: To investigate the biological and technical success outcomes of implant-supported fixed dental prostheses with and without cantilevers, after a minimum of one year loading.

Material and methods: One hundred and seven subjects with 128 cantilever FDPs (cFDP) supported by 132 implants were compared with 99 individuals with 144 non-cantilever FPDs (ncFDPs) supported by 203 implants. Outcomes such as marginal bone loss from FDP insertion to final follow-up as well as frequency and extent of biological and technical complications were investigated and correlated with patient, site, implant and FDP design characteristics.

Results: The cFDPs were followed for average of 51 months (1551 days, SD ± 977), and ncFPDs for 49 months (1483 days, SD ± 809 days). Implant survival and success rates were 96.7% and 87.9% for implant supporting cFDPs, and 99.5% and 92.6% for ncFDPs. There was no significant difference in overall bone loss between cFDPs and ncFDPs (cantilever side: 0.58, SD ± 1.16 - non-cantilever side: 0.59, SD ± 0.99), but implants in the cantilever group lost significantly more bone in the posterior mandible (0.50 SD ± 1.3 mm for cFDPs and 0.24 SD ± 0.80 mm for ncFDPs). Within the cantilever group, cantilever arm length and implant location had an influence on bone loss. Regardless of the presence of cantilever, implants associated with technical complications had a higher rate of biological complications as well. Furthermore, the length of the cantilever arm was positively correlated with implant failure, technical complications and bone loss ≥1.5 mm (P = 0.011, <0.001, and 0.007).

Conclusion: Overall implants can be successfully used to support cantilever FDPs. However, there are technical and biological implications which appear inter-related.

Keywords: biological complications; cantilevers; dental implants; implant-supported fixed partial dentures; peri-implant bone loss; technical complications.

Publication types

  • Comparative Study

MeSH terms

  • Alveolar Bone Loss / epidemiology
  • Dental Implantation, Endosseous
  • Dental Prosthesis Design
  • Dental Prosthesis, Implant-Supported*
  • Dental Restoration Failure
  • Denture Design
  • Denture, Partial, Fixed*
  • Female
  • Hong Kong / epidemiology
  • Humans
  • Male
  • Middle Aged
  • Retrospective Studies
  • Treatment Outcome