Assesment of changes in the sagittal pharyngeal airway dimensions post twin-block therapy using polar planimeter

Abstract

Background and Aim: An inordinate percentage of orthodontic patients present with Class II mandibular deficient problems. Mandibular deficiency is one of the major risk factors for developing obstructive sleep apnea (OSA). If functional appliance therapy for mandibular development also increases the pharyngeal airway dimensions the risk for developing OSA in these patients will be minimized. The aim of the present study is to evaluate the changes in the sagittal pharyngeal airway dimensions (SPAD) after twin-block functional appliance therapy in adolescent patients with mandibular retrognathism, utilizing linear, and area measurements. Materials and Methods: A total of 14 patients with an age range of 12–14 years, both the genders having skeletal Class II malocclusion with a deficient mandible were selected and twin-block functional therapy was initiated. Lateral cephalograms were taken at the start of functional jaw orthopedic treatment (time point T1) and at its completion (time point T2) after 4–5 months. Specific areas and distances were measured and analyzed. Results: The area measures increased significantly while the linear measurements showed a non significant increase. The oropharynx (P = 0.008) area displayed the most significant increase followed by nasopharynx (P = 0.014) and laryngopharynx (P = 0.028). Conclusion: Functional appliance therapy utilizing twin-block appliance in Class II malocclusion patients with retrognathic mandible was efficient in increasing the SPAD.

Keywords

• class ii
• obstructive sleep apnea
• polar planimeter