title: Resonance frequency analysis of implants subjected to immediate or early functional occlusal loading. Successful vs. failing implants.
abstract: OBJECTIVE
  The objective of this study was to analyze the development of implant stability by repeated resonance frequency analysis (RFA) measurements during 1 year in 23 patients treated according to an immediate/early-loading protocol. The objective was also to evaluate the possible differences between failing and successful implants.
  
  
  METHODS
  Eighty-one Brånemark System implants were placed in 23 patients for immediate/early-occlusal loading in all jaw regions. Thirty of the implants were placed in extraction sockets and 62 were subjected to GBR procedures. Apart from clinical and radiographic examinations, the patients were followed with RFA at placement, prosthesis connection and after 1-3, 6 and 12 months. Statistical analyses were carried out to study the possible differences between implants that failed during the study period and implants that remained successful.
  
  
  RESULTS
  Nine implants failed (11.2%) during the 1 year of loading. RFA showed a distinct different pattern between the implants that remained stable and the implants that were lost. The implants that failed during the course of the study showed a significantly lower stability already after 1 month.
  
  
  CONCLUSIONS
  Within the limitations of this study, it is concluded that failing implants show a continuous decrease of stability until failure. Low RFA levels after 1 and 2 months seem to indicate an increased risk for future failure. This information may be used to avoid implant failure in the future by unloading implants with decreasing degree of stability with time as diagnosed with the RFA technique.
authors.affiliation: Department for Fixed and Removable Prosthodontics, University of Zurich, Zurich, Switzerland. glauser@zzmk.unizh.ch
authors.forename: Roland
authors.initials: R
authors.lastname: Glauser
authors.forename: Lars
authors.initials: L
authors.lastname: Sennerby
authors.forename: Neil
authors.initials: N
authors.lastname: Meredith
authors.forename: Andreas
authors.initials: A
authors.lastname: Rée
authors.forename: AnnaKarin
authors.initials: A
authors.lastname: Lundgren
authors.forename: Jan
authors.initials: J
authors.lastname: Gottlow
authors.forename: Christoph H F
authors.initials: CH
authors.lastname: Hämmerle
mesh_terms: D003758:Dental Implantation, Endosseous / Q000379:methods; D015921:Dental Implants; D003768:Dental Occlusion, Centric; D017268:Dental Prosthesis Retention; D019094:Dental Prosthesis, Implant-Supported; D019232:Dental Restoration Failure; D003799:Dental Stress Analysis; D006801:Humans; D013997:Time Factors; D014732:Vibration; D016474:Weight-Bearing
chemical_list: D015921:Dental Implants