Relationship between morphological characteristics of hyoid bone and mandible in Japanese cadavers using three-dimensional computed tomography

Abstract

The aim of this study is to obtain a quantitative anatomical description of the hyoid bone and mandible using three-dimensional computed tomography. Hyoid bones were obtained from a total of 101 cadavers varying in age from 67 to 102 years. The percentage of symmetrical U-type and asymmetrical-type hyoid bones was low compared with symmetrical V type (14.9, 15.8, and 69.3 %, respectively), and no significant sex difference was observed. We found bilateral nonfusion in cadavers of advanced age at a rate of 22.7 % and bilateral complete fusion at a rate of 51.5 %. There were significant differences in metric variables (length and width) between males and females, but no significant differences in width among the different fusion types. There was no significant interaction effect of sex and degree of fusion. Strong significant associations were observed between size (length and width) of the hyoid bone and mandible in the nonfusion group, while the complete fusion group revealed a moderate correlation. We also investigated the hypothesis that the junction between the hyoid body and greater horn plays an important role in the movement of bones that have not yet ossified. However, no statistical difference was observed in the width between the two greater horns. The degree of fusion of the greater horn with the hyoid body may also affect relations of interdependencies between the hyoid bone and mandible, an important component to consider when assessing risk factors in the development of masticatory and swallowing function.

Growth and sexual dimorphism of the hyoid bone and its relationship to the mandible from birth to 19 years: A three‐dimensional computed tomography study

“…Sexual dimorphism in size and shape have been reported (Fakhry et al, 2013; Urbanova et al, 2013), with a number of studies confirming that the dimensions of the male hyoid bone are larger in males than females, but such findings are based on postpubertal hyoid bone measurements (Okasi et al, 2018; Sameera & Rao, 2019; Urbanova et al, 2013). Overall, our findings are generally consistent with sex‐specific differences reported that include the following dimensions: wider distance between the two greater cornua with males having greater width (Urbanova et al, 2013); wider hyoid body in males (distance between the left and right central points of junction of the greater cornu and the hyoid body) (Okasi et al, 2018; Vohra & Kulkarni, 2017); greater length of the greater cornu in males (Vohra & Kulkarni, 2017), specifically the left greater cornu (Okasi et al, 2018); and the common V‐shaped hyoid angle in females (Urbanova et al, 2013), formed by the intersection of lines extending between the two greater cornu, despite inconsistencies in findings on significance (Ichijo et al, 2016; Okasi et al, 2018).…”

“…The hyoid bone's unique disarticulation to other bony structures, and its unfused components prior to age 20, allow a greater influence on its growth and positions by its structural and functional needs in relation to the mandible and the larynx (Orsbon et al, 2018). In a 3D CT study of Japanese cadavers (ages 67-102 years), Ichijo et al (2016) reported a strong significant correlation between size (length and width) of the hyoid bone and the mandible in cadavers with nonfused hyoid bones and only moderate correlation in those in which the hyoid bone had completely fused.…”

“…Structurally, the hyoid body fuses to the right and left greater cornua after a protracted period of time in most individuals (Fisher et al, 2016; Kanetaka et al, 2011). Though hyoid bone fusion is typically absent prior to age 20, it does not occur in everyone during older adulthood, for unknown reasons (Fisher et al, 2016; Ichijo et al, 2016). While the sex‐specific timing of hyoid bone fusion and hyoid bone density has been explored across the lifespan (e.g., Fisher et al, 2016), knowledge on the three‐dimensional (3D) growth of the hyoid body and its greater cornua, particularly during early childhood, is scant (Harun et al, 2007; Sameera & Rao, 2019; Sheng et al, 2009; Vohra & Kulkarni, 2017).…”

“…While the sex‐specific timing of hyoid bone fusion and hyoid bone density has been explored across the lifespan (e.g., Fisher et al, 2016), knowledge on the three‐dimensional (3D) growth of the hyoid body and its greater cornua, particularly during early childhood, is scant (Harun et al, 2007; Sameera & Rao, 2019; Sheng et al, 2009; Vohra & Kulkarni, 2017). Also, although the hyoid bone responds to surgical intervention of mandibular deformities by adapting to the mandible's new placement (Kamano, Terajima, Kitahara, & Takahashi, 2017), given its functional relationship to the mandible as mediated by their attachments to the tongue, knowledge on how the position of the hyoid bone relative to the mandible changes across typical development is limited (Ichijo et al, 2016; Mitani & Sato, 1992; Okasi et al, 2018). Thus, the study and quantification of the growth of the hyoid bone and the relational growth of the hyomandibular complex in typically developing individuals are warranted.…”

Mandibular Ramus linear measurements as an Indicator of Chronological Age and Sex in Egyptian Population

“…[13] stated that dietary factors affect human mandible development. Silva et al [14] and Ichijo et al [15] stated that ethnicity affects human mandible development and measurements. Filho et al [16] found that stressful lifestyles affect mandible development and function.…”