Hyoid bone position in relation to Mandibular rotation

Abstract

Aims This retrospective cephalometric study was designed to evaluate and correlate
the hyoid bone position and angulations in two groups of subjects exhibiting
vertical and horizontal mandibular rotation.
Material & method: Each group consisted of 50 subjects (25 males and 25 females)
with skeletal class I pattern. Cephalometric data were obtained and four
measurements were used to locate the hyoid bone in 3 aspects 1. Vertical, 2.
Horizontal and 3. Angular. Thirteen angular and linear measurements were used
to evaluate mandibular rotation and facial morphology.
Result: There were statistically significant differences in vertical position, horizontal
distances and angulations of hyoid bone measurements between the vertical and
horizontal group subject (P<0.05). These measurements were significantly
correlated with mandibular rotation angles.
Conclusion: In vertical mandibular rotation group subjects, the hyoid bone showed
to be more inferior and posterior position with downward inclination. While in
horizontal mandibular rotation group subjects, the hyoid bone was more superior
and anterior position with relatively upward angulations.