title: Maxillary molar intrusion with fixed appliances and mini-implant anchorage studied in three dimensions.
abstract: The intrusion of an overerupted maxillary molar using traditional orthodontic treatment is a real challenge. The aim of this study was to investigate the envelope of intrusive movements of a maxillary molar in cases using mini-implants as anchorage with partial or full-mouth fixed edgewise appliances. The cusp tips of the pretreatment and postintrusion dental casts were recorded by a three-dimensional (3D) digitizer. The 3D data of the serial dental casts were analyzed to distinguish the direction and magnitude of individual tooth movement. The mean intrusive movement of the maxillary first molars was three to four mm, with a maximum of over eight mm. For the adjacent maxillary second molars and second premolars, the amount of intrusion was two mm and 1-2 mm, respectively. This study demonstrated that significant true intrusion of maxillary molars could be obtained in a well-controlled manner by using fixed appliances with titanium mini-implants as bony anchorage.
authors.affiliation: Department of Orthodontics, School of Dentistry, College of Medicine, National Taiwan University, Taipei, Taiwan, ROC.
authors.forename: Chung-Chen Jane
authors.initials: CC
authors.lastname: Yao
authors.forename: Jang-Jaer
authors.initials: JJ
authors.lastname: Lee
authors.forename: Hsing-Yu
authors.initials: HY
authors.lastname: Chen
authors.forename: Zwei-Chieng Jenny
authors.initials: ZC
authors.lastname: Chang
authors.forename: Hsin-Fu
authors.initials: HF
authors.lastname: Chang
authors.forename: Yi-Jane
authors.initials: YJ
authors.lastname: Chen
mesh_terms: D000293:Adolescent; D000328:Adult; D000539:Alveolar Process / Q000601:surgery; D001860:Bone Plates; D001863:Bone Screws; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008437:Maxilla; D008904:Miniaturization; D003765:Models, Dental; D008963:Molar / Q000503:physiopathology*; D052280:Orthodontic Anchorage Procedures / Q000295:instrumentation*; D016382:Orthodontic Appliance Design; D009967:Orthodontic Appliances; D021362:Palate, Hard / Q000601:surgery; D019736:Prostheses and Implants; D012189:Retrospective Studies; D014078:Tooth Eruption; D014087:Tooth Movement Techniques / Q000295:instrumentation*