Effects of a novel magnetic orthopedic appliance (MOA-III) on the dentofacial complex in mild to moderate skeletal class III children

Head & Face Medicine

Gang Shen¹  Rongjing Chen¹  Zheng Hu¹  Jing Feng¹  Ning Zhao¹ 

[1] Department of Orthodontics, Shanghai Key Laboratory of Stomatology, Shanghai No. 9 Hospital, ShanghaiJiaotong University School of Medicine, Shanghai, China

关键词: Adolescent;    Angle Class III;    Twin-block;    Magnetic;   

Others  :  1231229
DOI  :  10.1186/s13005-015-0092-7

 received in 2015-01-15, accepted in 2015-10-06,  发布年份 2015

【 摘 要 】

Introduction

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.

【 授权许可】

   
2015 Zhao et al.

【 图 表 】

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