• Batool Ali The Aga Khan University Hospital, Karachi
  • Attiya Shaikh The Aga Khan University Hospital, Karachi
  • Mubassar Fida The Aga Khan University Hospital, Karachi


Background: Functional appliances have been used since many decades for the correction of mandibular retrognathism. Similar oral appliances are a treatment modality for patients with Obstructive sleep apnea. Hence, interception at the right age with these growth modification appliances might benefit a child from developing long term respiratory insufficiency. Therefore, the purpose of our study was to assess the short term effects of Twin block appliance (CTB) on pharyngeal airway size in subjects with skeletal Class II pattern in a sample of Pakistani population. Methods: A retrospective study was conducted from orthodontic records of 62 children (31 males, 31 females) with retrognathic mandibles using lateral cephalograms obtained at initial visit and after CTB treatment. Paired t-test was used to compare the pre-functional and post-functional treatment airway size. Independent sample t-test was used for comparison between the genders and statistical significance was kept at ≤0.05. Results: The upper airway width (p<0.001), nasopharyngeal depth (p=0.03) and upper airway thickness (p=0.008) was substantially improved after CTB treatment. Males showed a greater increase in upper airway width (p= 0.03) and nasopharyngeal depth (p=0.01) in comparison to the females. Conclusion: Functional appliance therapy can improve the narrow pharyngeal airway of growing children presenting with deficient mandibles having Class II skeletal pattern.


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