title: Evaluation of two different resonance frequency devices to detect implant stability: a clinical trial.
abstract: BACKGROUND
  Resonance frequency analysis (RFA) provides a non-invasive assessment of implant stability. The established RFA device uses electronic technology, whereas a recently developed device uses magnetic technology. The goal of this clinical trial was to evaluate the ability of the magnetic RFA device to detect changes in stability during early healing following implant placement and to determine whether the implant stability quotient (ISQ) values obtained correlated with those made with the electronic device.
  
  
  METHODS
  RFA assessments were performed using electronic- and magnetic-based devices on 34 non-submerged titanium dental implants in 17 patients. Each patient received two implants in the posterior maxilla or mandible. Implant stability was measured at placement and weekly until week 6, when implants received provisional crowns, and at 12 weeks, when definitive crowns were cemented. During each visit, measurements were taken three times and averaged to obtain a single representative ISQ for each device.
  
  
  RESULTS
  At placement, the mean ISQ obtained with the electronic device was 61.9 (95% confidence interval [CI], 59.4 to 64.3); it increased to 63.2 (95% CI, 61.2 to 65.2) at 12 weeks. With the magnetic device, the mean ISQs were 70.6 (95% CI, 68.4 to 72.8) and 75.9 (95% CI, 74.2 to 77.7), respectively. Both devices indicated a pattern of decreased mean stability from 1 to 3 weeks post-placement, small fluctuations in mean ISQ from 3 to 6 weeks, and significantly increased mean stability from 6 to 12 weeks. For the complete set of implant measures across all weeks, the paired electronic and magnetic ISQ values correlated significantly (r = 0.52; P <0.001).
  
  
  CONCLUSIONS
  This study demonstrates that changes in implant stability measured with the newer magnetic device correlate well with those found with the electronic device. Both devices confirmed the initial decreases in implant stability that occur following placement and identified an increase in stability during the first 6 weeks of functional loading.
authors.affiliation: Department of Periodontics, Dental School, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229-3900, USA. mariapv@cable.net.co
authors.forename: Pilar
authors.initials: P
authors.lastname: Valderrama
authors.forename: Thomas W
authors.initials: TW
authors.lastname: Oates
authors.forename: Archie A
authors.initials: AA
authors.lastname: Jones
authors.forename: James
authors.initials: J
authors.lastname: Simpson
authors.forename: John D
authors.initials: JD
authors.lastname: Schoolfield
authors.forename: David L
authors.initials: DL
authors.lastname: Cochran
mesh_terms: D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D003758:Dental Implantation, Endosseous; D015921:Dental Implants; D017268:Dental Prosthesis Retention; D019232:Dental Restoration Failure; D003799:Dental Stress Analysis; D004582:Electronics, Medical / Q000295:instrumentation; D005260:Female; D006801:Humans; D008280:Magnetics / Q000295:instrumentation; D008297:Male; D008875:Middle Aged; D018709:Statistics, Nonparametric; D014732:Vibration
chemical_list: D015921:Dental Implants