Document Type : Original Article


Department of Orthodontics, Coorg Institute of Dental Sciences, Virajpet, Karnataka, India


Aim: Dental malocclusion and jaw misalignments are the foremost reasons for airway constriction. To facilitate anterior mandibular repositioning and the concomitant anterior positioning of the tongue can induce the expansion of the pharyngeal airway. The study aimed to compare comprehensive treatment outcomes of fixed and removable mandibular advancement appliances on the width of the pharyngeal airway space.
Methods: Twenty growing patients with skeletal Class II malocclusion were placed into two groups: Advansync2 and twin block. Patients were advised to use mandibular advancement appliances (MAA) for 9–12 months. Lateral cephalograms and the Epworth Sleepiness Scale (ESS) were evaluated to assess alterations in the pharyngeal airway space and quality of sleep at two intervals. The chi-square test, one-way ANOVA and Duncan’s post hoc test were used for statistical analysis. P-values<0.05 were considered as significant.
Results: Based on the results, only the change in PNS-V measurements indicated a significant difference between appliances. Advansync2 showed more change (0.70±2.45 mm) compared to twin block (-1.80±2.34 mm), indicating a statistically significant difference (p=0.032).
Conclusion: A significant reduction in the ESS score in both groups was observed without any significant differences between them.


Main Subjects

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