title: Application of a wireless resonance frequency transducer to assess primary stability of orthodontic mini-implants: an in vitro study in pig ilia.
abstract: OBJECTIVE
  The aim of the study was to evaluate whether resonance frequency analysis (RFA) using a wireless transducer can be used to assess the primary stability of orthodontic mini-implants.
  
  
  METHODS
  Fifteen orthodontic mini-implants were placed in three ilium bone segments of country pigs. The wireless resonance frequency transducer was bonded to the head of the mini-implants, and RFA values of the mini-implants in bone were detected and converted into implant stability quotient (ISQ) values by the RFA monitor. In addition, the percussion test value, peri-implant radiographic bone density, and cortical bone thickness were measured.
  
  
  RESULTS
  The ISQ values of mini-implants correlated linearly with peri-implant radiographic bone density (r = 0.92, P < .0001), cortical bone thickness (r = 0.90, P < .0001), and percussion test values (r = -0.91, P < .0001), respectively. In addition, by means of the calculation of 99% confidence intervals, the absolute values of the three correlation coefficients ranged from 0.61 to 0.98.
  
  
  CONCLUSIONS
  This in vitro animal study showed that the presented RFA method using a wireless transducer might have potential to provide an alternative noninvasive assessment of the primary stability of an orthodontic mini-implant.
authors.affiliation: Department of Orthodontics, Heinrich-Heine University Düsseldorf, Germany. dr.yuyusu@googlemail.com
authors.forename: Yu-Yu
authors.initials: YY
authors.lastname: Su
authors.forename: Benedict
authors.initials: B
authors.lastname: Wilmes
authors.forename: Ralf
authors.initials: R
authors.lastname: Hönscheid
authors.forename: Dieter
authors.initials: D
authors.lastname: Drescher
mesh_terms: D000818:Animals; D015519:Bone Density / Q000502:physiology; D054893:Cone-Beam Computed Tomography; D003722:Dental Alloys / Q000737:chemistry; D015921:Dental Implants; D055119:Elastic Modulus; D055590:Electromagnetic Phenomena; D007085:Ilium / Q000000981:diagnostic imaging / Q000601:surgery*; D052280:Orthodontic Anchorage Procedures / Q000295:instrumentation*; D010474:Percussion; D010865:Pilot Projects; D013552:Swine; D014025:Titanium / Q000737:chemistry; D014159:Transducers; D014732:Vibration
chemical_list: D003722:Dental Alloys; D015921:Dental Implants; D014025:Titanium