Effect of cervical headgear wear on dynamic measurement of head position

Cervical Headgear Effects on the Morphology of the Cervical Vertebrae and Cervical Posture

OBJECTIVE

To test the hypothesis that use of cervical headgear has an important effect on the morphology of the cervical vertebrae and cervical posture.

MATERIALS AND METHODS

The material consisted of pretreatment and posttreatment lateral cephalograms and initial hand-wrist films of 30 subjects who were receiving cervical headgear therapy. Preobservation and postobservation control cephalograms and preobservation hand-wrist films of 15 untreated subjects served as controls. The average treatment time for the treatment group was 9.06 +/- 1.02 months, and the average observation period for the control group was 10.0 +/- 1.1 months. A paired t-test was applied to compare the changes occurring during the examination and observation periods in both groups. In addition, Student's t-test was performed to assess the differences between the groups.

RESULTS

The results of the paired t-test showed that within each group there were statistically significant differences in the majority of measurements concerning the morphology of the cervical vertebrae, whereas the measurements concerning cervical posture showed no significant changes in either group. According to the results of the Student's t-test, however, no statistically significant changes between the treatment and control group were present except with regard to two measurements.

CONCLUSIONS

Changes in the cervicovertebral morphology in the treatment group were achieved more by growth than by cervical headgear treatment. Although high individual variations were found in postural variables, cervical posture did not change over a period of 9 months either in the treatment group or in the control group.

Reproducibility of airway dimensions and tongue and hyoid positions on lateral cephalograms

INTRODUCTION

The aim of this study was to evaluate the reproducibility of airway dimensions and tongue and hyoid positions on lateral cephalometric radiographs.

METHODS

Three lateral cephalograms each of 30 patients were obtained in natural head positions at 30-minute intervals. Twelve measurements, including pharyngeal airway dimensions and tongue and hyoid positions, were taken. The relationships between 3 sets of measurements were evaluated by using repeated analysis of variance, Dahlberg's method error formula, and correlation coefficient.

RESULTS

No statistically significant differences were found between the 3 sets of measurements with the repeated analysis of variance (P > .05). Correlation coefficient values ranged between 0.964 (vertical position of the hyoid) and 0.683 (hypopharyngeal airway width). The average method error was 1.22 mm.

CONCLUSIONS

The results suggest that airway dimension and tongue- and hyoid-position measurements are highly reproducible on natural-head-position cephalograms.