title: Measurement of mini-implant stability using resonance frequency analysis.
abstract: OBJECTIVE
  To investigate whether resonance frequency analysis (RFA) is suitable to measure orthodontic mini-implant stability. Implant size significantly affects the level of resonance frequency. Regarding the operating mode of RFA, it has to be proven whether the resonance frequency of mini-implants in bone fits the range of frequency emitted by the Osstell ISQ device.
  
  
  METHODS
  For this purpose the SmartPegs in the Osstell ISQ device were modified to fit with the inner screw thread of orthodontic mini-implants, and 110 mini-implants were inserted into porcine pelvic bone. RFA was performed parallel and perpendicular to the run of superficial bone fibers. A suitability test, Periotest, was also performed in the same directions. Compacta thickness was measured using cone-beam computed tomography. Correlation tests and linear regression analysis were carried out between the three methods.
  
  
  RESULTS
  The RFA showed a mean Implant Stability Quotient value of 36.36 ± 2.67, and the Periotest mean value was -2.10 ± 1.17. The differences between the two directions of measurement were statistically significant (P > .001) for RFA and the Periotest. There was a high correlation between RFA and the Periotest (r  =  -0.90) and between RFA and compacta thickness (r  =  0.71). The comparison between the Periotest and compacta thickness showed a correlation coefficient of r  =  -0.64.
  
  
  CONCLUSIONS
  The present results suggest that RFA is feasible as a measurement method for orthodontic mini-implant stability. As a consequence, it could be used for clinical evaluation of current stability and allow stability-related loading of mini-implants to reduce the failure rate.
authors.affiliation: Department of Orthodontics, Heinrich-Heine-University, Düsseldorf, Germany. Manuel.Nienkemper@uni-duesseldorf.de
authors.forename: Manuel
authors.initials: M
authors.lastname: Nienkemper
authors.forename: Benedict
authors.initials: B
authors.lastname: Wilmes
authors.forename: Agamemnon
authors.initials: A
authors.lastname: Panayotidis
authors.forename: Alexander
authors.initials: A
authors.lastname: Pauls
authors.forename: Vladimir
authors.initials: V
authors.lastname: Golubovic
authors.forename: Frank
authors.initials: F
authors.lastname: Schwarz
authors.forename: Dieter
authors.initials: D
authors.lastname: Drescher
mesh_terms: D000818:Animals; D015519:Bone Density; D054893:Cone-Beam Computed Tomography; D015921:Dental Implants; D017268:Dental Prosthesis Retention; D003799:Dental Stress Analysis; D005240:Feasibility Studies; D016014:Linear Models; D052280:Orthodontic Anchorage Procedures / Q000295:instrumentation*; D016348:Osseointegration; D015203:Reproducibility of Results; D018709:Statistics, Nonparametric; D013552:Swine; D014732:Vibration
chemical_list: D015921:Dental Implants