Shanghai Journal of Stomatology ›› 2018, Vol. 27 ›› Issue (6): 607-611.doi: 10.19439/j.sjos.2018.06.009

• Original Articles • Previous Articles     Next Articles

Changes of airway before and after Twin-block treatment in patients with mandibular retrusion

WANG Wei, MO Shi-cheng, WANG Lin   

  1. Jiangsu Key Laboratory of Oral Diseases, Nanjing Medical University; Department of Orthodontics, Affiliated Hospital of Stomatology, Nanjing Medical University. Nanjing 210029, Jiangsu Province, China
  • Received:2018-01-22 Online:2018-12-25 Published:2019-01-11
  • Supported by:
    江苏省优势学科(PAPD,2018-87); 江苏省医学重点学科(口腔正畸学zdxka2016026)

Abstract: PURPOSE: To observe the changes of upper airway and the effect of different tongue position on upper airway volume before and after Twin-block treatment in patients with Class II division 1 malocclusion and mandibular retrusion. METHODS: Thirty-three patients (ages:11.3±0.89) with Class II division 1 malocclusion and mandibular retrusion were included in the study and divided into 2 groups, the control group (12 patients) and experimental group (21 patients). In the experimental group, according to the tongue position shown on cone-beam CT (CBCT), the patients were sub-divided into lower tongue position group and higher tongue position group. Patients in the experimental group were treated with Twin-block appliance, and CBCT was taken before treatment and 8 months after treatment. Patients in the control group underwent CBCT at the first month and eighth month. The changes of oropharyngeal airway volume and the minimal cross-sectional area were measured by using Dolphin software. SPSS 24 software package was used for t test and one-way variance analysis. RESULTS: After 8 months, the airway volume and the minimal cross sectional area of the oropharynx in the control group were not significantly changed, but significantly increased in the experimental group (P<0.001), especially in the higher tongue position group (P<0.05). CONCLUSIONS: Twin-block can significantly increase the oropharyngeal airway volume and minimum cross-sectional area in patients with Class II division 1 malocclusion and mandibular retrusion. In addition, mandibular advancement dose not correlate with airway improvement and the right tongue position has an obvious effect on airway opening in mandibular advancement.

Key words: Twin-block appliance, Class II division 1 malocclusion, Tongue, Airway volume, Minimal cross sectional area

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