TITLE:
Hyoid Bone Position as an Etiological Factor in Mandibular Divergence and Morphology
AUTHORS:
Tiffany Pei-Jou Chen, Falon Rodhisky, Shuying Sue Jiang, Thomas J. Cangialosi
KEYWORDS:
Hyoid Bone, Mandibular Divergence, Orthopedic, Surgery
JOURNAL NAME:
Open Journal of Orthopedics,
Vol.12 No.1,
January
24,
2022
ABSTRACT: Objectives: The objective is to determine whether there are differences in the position of the hyoid
bone at rest in natural head position in subjects with mandibular hyperdivergence and to evaluate whether there are differences in hyoid position and
antegonial notch depth in mandibular hyperdivergent males and females. Methods
and Materials: This is a retrospective cohort study involving a review of
lateral cephalometric radiographs of 45 adult men and women with mandibular
hyperdivergency. Hyperdivergency was determined by cephalometric ranges of:
SN-GoGn as least +2 SD from normal, Y-axis, PP-GoGN, and gonial angle greater
than +1SD from normal. A group of 45 normodivergent adults served as a control,
with cephalometric ranges of: SN-GoGn within ±1 SD of normal, with only one measurement of the other three between +1
and +1.5 standard deviations. A custom digital cephalometric analysis, the
Hyoid Analysis, was designed, to measure the vertical and horizontal position
and inclination of the hyoid and the antegonial notch depth. Results: In
hyperdivergent subjects, the posterior aspect of the hyoid is located lower and
more posterior, compared to the control group, while there is no difference in
position of the anterior surface of the hyoid and the antegonial notch is 0.6 mm
deeper. In males, the posterior aspect of hyoid is lower by 8.5 mm, while
the anterior surface is located 9.0 mm lower.
In males, the hyoid is inclined more steeply than in females by 4.4 degrees and
the antegonial notch is deeper than in females by 0.6 mm. Conclusions: There are differences in hyoid bone position and mandibular morphology in
hyperdivergent subjects compared to normodivergent subjects and in males
compared to females.