title: Treatment and posttreatment dentoalveolar changes following intrusion of mandibular molars with application of a skeletal anchorage system (SAS) for open bite correction.
abstract: The skeletal anchorage system (SAS) consists of titanium anchor plates and monocortical screws that are temporarily implanted in either the maxilla or the mandible as absolute orthodontic anchorage. With SAS, anterior open bite can be improved by the counterclockwise rotation of the mandible, accompanied by the intrusion of molars. The present study was designed to evaluate treatment and posttreatment dentoalveolar changes following the intrusion of mandibular molars. Nine adult open bite patients (7 women and 2 men) successfully treated with SAS were included in the following study. The amount of intrusion, relapse, and dentoalveolar changes were measured on cephalometric radiographs, panoramic radiographs, and dental casts. The results of this study were as follows: (1) the average amount of intrusion of the mandibular first and second molars was 1.7 mm and 2.8 mm, respectively; (2) the average relapse rates were 27.2% at the first molars and 30.3% at the second molars; (3) there were no significant changes in crestal bone heights, clinical crown length, or root length; and (4) counterclockwise rotation of the mandible and decrease of anterior facial height were observed during treatment. Thus, it was concluded that SAS would be a valid modality to intrude mandibular molars for correction of open bite.
authors.affiliation: Division of Orthodontics and Dentofacial Orthopedics, Tohoku University Graduate School of Dentistry 4-1, Seiryo-machi, Aoba-ku Sendai, 980-8575, Japan. sugahara@mail.cc.tohoku.ac.jp
authors.forename: Junji
authors.initials: J
authors.lastname: Sugawara
authors.forename: Un Bong
authors.initials: UB
authors.lastname: Baik
authors.forename: Mikako
authors.initials: M
authors.lastname: Umemori
authors.forename: Ichiro
authors.initials: I
authors.lastname: Takahashi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nagasaka
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kawamura
authors.forename: Hideo
authors.initials: H
authors.lastname: Mitani
mesh_terms: D000293:Adolescent; D000328:Adult; D000539:Alveolar Process / Q000033:anatomy & histology; D002508:Cephalometry; D003758:Dental Implantation, Endosseous; D015921:Dental Implants; D005145:Face / Q000033:anatomy & histology; D005260:Female; D006801:Humans; D008297:Male; D008334:Mandible; D003765:Models, Dental; D008963:Molar; D024343:Open Bite / Q000628:therapy*; D016382:Orthodontic Appliance Design; D009967:Orthodontic Appliances; D012008:Recurrence; D012391:Root Resorption / Q000209:etiology; D019228:Tooth Crown / Q000033:anatomy & histology; D014087:Tooth Movement Techniques / Q000009:adverse effects / Q000295:instrumentation*; D016896:Treatment Outcome; D014716:Vertical Dimension
chemical_list: D015921:Dental Implants