Sexual dimorphism in hypopharyngeal airway space and effective length of mandible with twin block appliance therapy: A prospective study

Abstract

To evaluate changes in hypopharyngeal airway space and effective length of mandible in skeletal Class II patients following Twin Block Appliance (TBA) therapy. Further, the study also aims to compare the post functional changes being observed between males and females. This is a prospective study on 15 Pre-adolescents (08 males and 07 females; mean age: 10.75 ± 0.91years) who underwent functional jaw orthopaedics with TBA. Lateral cephalogram at Pre treatment stage (T1) and post functional phase of TBA (T2) were obtained. The cephalometric parameters were measured and paired t test was done for comparison of pre and post functional changes. The mean period of functional phase of TBA therapy was 18 ± 02 months. The cephalometric changes post functional jaw orthopaedics were statistically insignificant when compared males Vs females (P > 0.05). However, mean increase of in the effective length of mandible and hypopharyngeal space (T2-T1) was 4.0± 1.16 mm and 1.47±0.57 mm respectively, which were statistically highly significant (P<0.5). 1. TBA therapy in skeletal Class II patients significantly increases the effective mandibular length and hypo-pharyngeal space post functional phase; 2. No significant differences were observed between males and females with respect to post functional cephalometric changes in mandibular length and hypopharyngeal space.