title: Ability of mini-implant-facilitated micro-osteoperforations to accelerate tooth movement in rats.
abstract: BACKGROUND
  Although current techniques for accelerated tooth movement often involve invasive surgical procedures, micro-osteoperforations (MOPs) using mini-implants may facilitate orthodontic tooth movement without raising flaps, reduce surgical risks, and increase patient acceptance. In this study, we evaluated the effectiveness of mini-implant-facilitated MOPs in inducing accelerated tooth movement and investigated the potential risks for root resorption.
  
  
  METHODS
  Five MOPs were placed on the left side around the maxillary first molars in 6 rats using an automated mini-implant driver, whereas the right side received no MOPs as the control. Closed-coiled springs were secured from incisors to first molars for orthodontic tooth movement. Tooth movement was measured, and samples underwent radiologic and histologic analyses.
  
  
  RESULTS
  The MOP side exhibited a 1.86-fold increase in the rate of tooth movement with decreased bone density and bone volume around the first molars compared with the control side. Hematoxylin and eosin and tartrate-resistant acid phosphatase analyses showed increased numbers of osteoclasts as well as new bone formation. Three-dimensional volumetric analysis of all 5 roots of the maxillary first molars demonstrated no statistically significant difference in root volumes.
  
  
  CONCLUSIONS
  Mini-implant-facilitated MOPs accelerated tooth movement without increased risk for root resorption and therefore may become a readily available and efficient treatment option to shorten orthodontic treatment time with improved patient acceptance.
authors.affiliation: Resident, Section of Orthodontics, School of Dentistry, University of California at Los Angeles, Los Angeles, Calif.
authors.forename: Tracy
authors.initials: T
authors.lastname: Cheung
authors.affiliation: Graduate student, Division of Oral Biology, University of California at Los Angeles, Los Angeles, Calif.
authors.forename: Juyoung
authors.initials: J
authors.lastname: Park
authors.affiliation: Graduate student, School of Dentistry, University of California at Los Angeles, Los Angeles, Calif.
authors.forename: Deborah
authors.initials: D
authors.lastname: Lee
authors.affiliation: Graduate student, School of Dentistry, University of California at Los Angeles, Los Angeles, Calif.
authors.forename: Catherine
authors.initials: C
authors.lastname: Kim
authors.affiliation: Graduate student, School of Dentistry, University of California at Los Angeles, Los Angeles, Calif.
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Olson
authors.affiliation: Assistant project scientist, Section of Orthodontics, School of Dentistry, University of California at Los Angeles, Los Angeles, Calif.
authors.forename: Shadi
authors.initials: S
authors.lastname: Javadi
authors.affiliation: Director, Pathology and Laboratory Medicine, Division of Laboratory Animal Medicine, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, Calif.
authors.forename: Gregory
authors.initials: G
authors.lastname: Lawson
authors.affiliation: Training manager, Division of Laboratory Animal Medicine, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, Calif.
authors.forename: James
authors.initials: J
authors.lastname: McCabe
authors.affiliation: Clinical associate professor, Section of Orthodontics, School of Dentistry, University of California at Los Angeles, Los Angeles, Calif.
authors.forename: Won
authors.initials: W
authors.lastname: Moon
authors.affiliation: Chair and professor, Section of Orthodontics, School of Dentistry, University of California at Los Angeles, Los Angeles, Calif.
authors.forename: Kang
authors.initials: K
authors.lastname: Ting
authors.affiliation: Assistant professor, Section of Orthodontics, School of Dentistry, University of California at Los Angeles, Los Angeles, Calif. Electronic address: chong@dentistry.ucla.edu.
authors.forename: Christine
authors.initials: C
authors.lastname: Hong
mesh_terms: D000818:Animals; D008297:Male; D008334:Mandible / Q000000981:diagnostic imaging / Q000601:surgery; D008963:Molar / Q000000981:diagnostic imaging / Q000601:surgery; D009969:Orthodontic Wires; D051381:Rats; D017207:Rats, Sprague-Dawley; D012391:Root Resorption / Q000000981:diagnostic imaging / Q000209:etiology; D014087:Tooth Movement Techniques / Q000295:instrumentation / Q000379:methods*; D055114:X-Ray Microtomography