title: Increasing the amount of corticotomy does not affect orthodontic tooth movement or root resorption, but accelerates alveolar bone resorption in rats.
abstract: The purpose of this study was to evaluate the relationships among the volume of bone cut during corticotomy, amount of tooth movement, volume of root resorption, and volume of the resultant alveolar bone resorption after tooth movement.
  
  
  
  Ten-week-old female Wistar rats were distributed into the corticotomy groups and a control group that underwent sham corticotomy. Two experiments employing two different orthodontic forces (10 or 25g) and experimental periods (14 or 21 days) were performed. The volumes of the bone cut by corticotomy were 0.1, 1.0, and 1.7mm3 in the 25g groups, and 1.0 and 1.7mm3 in the 10g groups. Nickel-titanium closed-coil springs were set on the maxillary left first molars to induce mesial movement. After orthodontic tooth movement, the amount of tooth movement, volume of root resorption, and volume of alveolar bone resorption were measured.
  
  
  
  Despite differences in the volume of bone cut among the different corticotomy groups, there were not significant differences in the amount of tooth movement and volume of root resorption between the control group and any of the corticotomy groups. However, higher volume of bone cut during corticotomy was significantly related to the decreased alveolar bone volume-in particular, to the reduced height of the alveolar bone crest after tooth movement.
  
  
  
  The volume of the alveolar bone cut during corticotomy does not affect tooth movement or root resorption in 10-week-old female Wistar rats; however, it may increase alveolar bone loss after tooth movement.
authors.affiliation: Department of Orthodontics and Dentofacial Orthopedics, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kurohama
authors.affiliation: Department of Orthodontics and Dentofacial Orthopedics, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Hotokezaka
authors.affiliation: Department of Orthodontics and Dentofacial Orthopedics, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.
authors.forename: Megumi
authors.initials: M
authors.lastname: Hashimoto
authors.affiliation: Department of Orthodontics and Dentofacial Orthopedics, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.
authors.forename: Takako
authors.initials: T
authors.lastname: Tajima
authors.affiliation: Department of Orthodontics and Dentofacial Orthopedics, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.
authors.forename: Kotaro
authors.initials: K
authors.lastname: Arita
authors.affiliation: Department of Orthodontics and Dentofacial Orthopedics, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.
authors.forename: Takanobu
authors.initials: T
authors.lastname: Kondo
authors.affiliation: Department of Orthodontics and Dentofacial Orthopedics, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.
authors.forename: Airi
authors.initials: A
authors.lastname: Ino
authors.affiliation: Department of Orthodontics and Dentofacial Orthopedics, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.
authors.forename: Noriaki
authors.initials: N
authors.lastname: Yoshida
mesh_terms: D016301:Alveolar Bone Loss / Q000209:etiology* / Q000473:pathology; D000539:Alveolar Process / Q000473:pathology / Q000601:surgery*; D000818:Animals; D000071538:Cortical Bone / Q000473:pathology / Q000601:surgery*; D005260:Female; D008963:Molar; D017208:Rats, Wistar; D012391:Root Resorption / Q000209:etiology*; D014087:Tooth Movement Techniques / Q000009:adverse effects / Q000379:methods*