title: The prognostic accuracy of resonance frequency analysis in predicting failure risk of immediately restored implants.
abstract: OBJECTIVE
  It is of imperative clinical significance to define a safe threshold for planned immediate implant restoration. The aim of this report was to evaluate the prognostic accuracy of resonance frequency analysis (RFA) measurements recorded at two different times (implant placement and 8-week post-implant placement) and to determine the optimal threshold value for predicting failure risk of immediately restored/loaded implants.
  
  
  METHODS
  Twenty-eight 8- or 9-mm-diameter implants were placed in either a fresh molar extraction socket or a healed site. An electronic RFA device was used to record the implant stability quotients (ISQs) at implant placement surgery, 8 weeks and 1 year. Receiver operating characteristic (ROC) analysis was used to identify the optimal cut-off level. Sensitivity and specificity were also determined at the selected cut-off value.
  
  
  RESULTS
  The area under the ROC curve for RFA at 8 weeks was 0.93 with a significant P-value (P = 0.001). The optimum cut-off value for detecting implant stability was 60.5 ISQ measured at 8 weeks, with sensitivity and specificity of 95.2% and 71.4%, respectively.
  
  
  CONCLUSIONS
  The implant stability measurements after 8 weeks showed a better accuracy in predicting implants that were at risk of failure than those taken at the time of implant placement.
authors.affiliation: Oral Implantology Research Group, Sir John Walsh Research Institute, School of Dentistry, University of Otago, 310 Great King Street, Dunedin, New Zealand.
authors.forename: Momen A
authors.initials: MA
authors.lastname: Atieh
authors.forename: Nabeel H M
authors.initials: NH
authors.lastname: Alsabeeha
authors.forename: Alan G T
authors.initials: AG
authors.lastname: Payne
authors.forename: Rohana K
authors.initials: RK
authors.lastname: de Silva
authors.forename: Donald S
authors.initials: DS
authors.lastname: Schwass
authors.forename: Warwick J
authors.initials: WJ
authors.lastname: Duncan
mesh_terms: D019250:Dental Implants, Single-Tooth; D019232:Dental Restoration Failure / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D057893:Immediate Dental Implant Loading; D008297:Male; D008334:Mandible / Q000601:surgery; D008875:Middle Aged; D008963:Molar; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted; D014159:Transducers; D014732:Vibration
keywords: ROC curve; dental implants; prognosis; sensitivity and specificity