Evaluation of cervical spine posture after functional therapy with twin-block appliances

Abstract

Objective: The aim of this study was to investigate the effect of the twin-block appliances to the cervical spine posture. Materials and Methods: Twenty-one skeletal Class II patients (11 female, 10 male; 13.31 ± 0.92) with mandibular retrusion were included in the study. Twin-block appliances with no expansion protocol were applied to all individuals. Cervical spine posture changes after treatment were evaluated by cephalograms. The differences between pre- and post-treatment measurements were evaluated by paired sample t-test. Results: No significant differences were observed after treatment, in the angle between the horizontal lines of the head (sella-nasion, anterior nasal spine-posterior nasal spine, and gonion and gnathion) and the upper and middle section of the spinal column (odontoid process tangent [OPT] and cerebral venous thrombosis [CVT]) (P > 0.05), while the increase of cervical curvature angle (OPT/CVT°) was found significant after the treatment (P = 0.009). Conclusion: A backward inclination of the middle segment of cervical column seems to be associated with the advancement of the mandible by twin-block treatment.