title: Success rate of mini- and micro-implants used for orthodontic anchorage: a prospective clinical study.
abstract: OBJECTIVE
  Whereas micro-implants have become a useful alternative as orthodontic anchorage elements in orthodontics, less is known about the clinical effectiveness of micro-implants. The aim of this prospective clinical study was to evaluate the success rate of micro-implants used for orthodontic anchorage.
  
  
  METHODS
  A total of 133 mini-implants (79 Abso Anchor, 54 Dual Top implants) placed in 49 patients to support orthodontic tooth movements were examined in the study. The majority of the implants were placed in the maxilla (82), followed by the vestibular (42) and lingual (nine) aspect of the mandible.
  
  
  RESULTS
  An overall cumulative survival rate of 86.8% (102/133) was found by Kaplan-Meier analysis. The failure rate between Dual Top implants (13%) and Abso Anchor implants (30.4%) differed significantly (P=0.0196; log-rank test). The cumulative failure rate of implants was found to be significantly higher when implants were placed in the lingual aspect of the mandible compared with the other localizations (P=0.0011; log-rank test). Clinical evaluation revealed successful dental movements when implants remained stable during the orthodontic therapy.
  
  
  CONCLUSIONS
  The present results confirm the effectiveness of orthodontic micro-implants used as anchorage elements.
authors.affiliation: Department of Cranio-Maxillofacial Surgery, University of Münster, Münster, Germany.
authors.forename: Dirk
authors.initials: D
authors.lastname: Wiechmann
authors.forename: Ulrich
authors.initials: U
authors.lastname: Meyer
authors.forename: André
authors.initials: A
authors.lastname: Büchter
mesh_terms: D000293:Adolescent; D000328:Adult; D004868:Equipment Failure; D005260:Female; D006801:Humans; D008297:Male; D008334:Mandible / Q000601:surgery; D008437:Maxilla / Q000601:surgery; D008875:Middle Aged; D052280:Orthodontic Anchorage Procedures / Q000295:instrumentation*; D016382:Orthodontic Appliance Design; D019516:Orthodontic Space Closure / Q000295:instrumentation; D016348:Osseointegration / Q000502:physiology; D011446:Prospective Studies; D013499:Surface Properties; D016019:Survival Analysis; D014087:Tooth Movement Techniques / Q000295:instrumentation; D016896:Treatment Outcome