ABSTRACT

Comparative examination of the position of the hyoid bone and its relation with dentofacial system according to its position on total of 45 patients with Class I, Class II D1 and Class III malocclusions. SNA, SNB and ANB, Go-Gn-SN angles are used as identification parameters for different malocclusions. 7 horizontal, 5 vertical and 5 angular measurements are evaluated in order to establish the position of the hyoid bone. SN plane is used as the reference plane. Mann-Whitney test is used to evaluate the measurements statistically. When Class I and Class II D 1 groups are compared, statistically significant differences are observed in At-H, H-CVT ,H-OP and A-H, N-H, PTR-H. When Class I and Class III groups are compared statistically significant differences are seen in At-H ve H-OP and A-H, N-H, PTR-H H measurements. In Class II D 1 malocclusion the position of the hyoid bone is found to be more posterior than normal and in Class III malocclusion more anterior than normal.