title: Effects of a novel magnetic orthopedic appliance (MOA-III) on the dentofacial complex in mild to moderate skeletal class III children.
abstract: BACKGROUND
  The objective of this study was to evaluate the changes of skeletal and dental structures in mild to moderate skeletal Class III children following the use of a new magnetic orthopedic appliance (MOA-III).
  
  
  METHODS
  A total of 36 patients (14 boys and 22 girls, mean age 9 years and 5 months) who presented with a mild to moderate skeletal Class III jaw discrepancy were treated with MOA-III. Another group of 20 untreated patients (9 boys and 11 girls, mean age 9 years and 2 months) with the same level of deformity served as the control group. The average treatment time was 6.6 months. Radiographs were taken at the same time intervals for both groups. A paired t test was used to determine the significant differences before and after treatment, and a two-sample t test was used to analyze the differences between the treatment and control groups.
  
  
  RESULTS
  The anterior crossbite in all subjects was corrected after MOA-III therapy. The maxillomandibular relationship showed favorable changes (ANB, Wits, overjet increased significantly, P < 0.001). The maxilla was anteriorly positioned (SNA, ptm-A, ptm-S increased significantly, P < 0.001) with clockwise rotation (PP-FH increased, P < 0.001). The mandible showed a slight downward and backward rotation (SNB decreased, P < 0.05, MP-SN, Y-axis increased, P < 0.05). The length of the mandibular body showed no significant changes (Go-Pg, P > 0.05). Significant upper incisor proclination and lower incisor retroclination were observed (UI-NA increased, P < 0.001, LI-NB, FMIA decreased, P < 0.001). The upper lip moved forward, and the lower lip moved backward (UL-EP increased, P < 0.001, LL-EP decreased, P < 0.05). In the control group, most of the parameters showed normal growth, except for some unfavorable mandibular skeletal and soft tissue changes (Go-Pg, Go-Co, MP-SN, N'-SN-Pg' increased, P < 0.001). Significant positive changes were induced with the MOA-III appliance compared to the untreated group.
  
  
  CONCLUSIONS
  The MOA-III was effective for the early treatment of a mild to moderate Class III malocclusion in children.
authors.affiliation: Department of Orthodontics, Shanghai Key Laboratory of Stomatology, Shanghai No. 9 Hospital, ShanghaiJiaotong University School of Medicine, Shanghai, China. zhaon1995@126.com.
authors.forename: Ning
authors.initials: N
authors.lastname: Zhao
authors.affiliation: Department of Orthodontics, Shanghai Key Laboratory of Stomatology, Shanghai No. 9 Hospital, ShanghaiJiaotong University School of Medicine, Shanghai, China. helen_fj@126.com.
authors.forename: Jing
authors.initials: J
authors.lastname: Feng
authors.affiliation: Department of Orthodontics, Shanghai Key Laboratory of Stomatology, Shanghai No. 9 Hospital, ShanghaiJiaotong University School of Medicine, Shanghai, China. orthohu@126.com.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Hu
authors.affiliation: Department of Orthodontics, Shanghai Key Laboratory of Stomatology, Shanghai No. 9 Hospital, ShanghaiJiaotong University School of Medicine, Shanghai, China. rongjingchen@126.com.
authors.forename: Rongjing
authors.initials: R
authors.lastname: Chen
authors.affiliation: Department of Orthodontics, Shanghai Key Laboratory of Stomatology, Shanghai No. 9 Hospital, ShanghaiJiaotong University School of Medicine, Shanghai, China. gangshen@126.com.
authors.forename: Gang
authors.initials: G
authors.lastname: Shen
mesh_terms: D000293:Adolescent; D002508:Cephalometry; D002648:Child; D005260:Female; D006801:Humans; D060328:Magnetic Phenomena; D008297:Male; D008313:Malocclusion, Angle Class III / Q000601:surgery*; D008334:Mandible; D008437:Maxilla; D008445:Maxillofacial Development; D016382:Orthodontic Appliance Design; D009984:Orthopedic Fixation Devices / Q000009:adverse effects*