Calcification of the stylohyoid complex in Londoners and Hong Kong Chinese.

Aim: To compare the prevalence and pattern of calcification of the stylohyoid complex in Hong Kong Chinese with that in London.
Methods: The panoramic radiographs of two consecutive series of patients attending the primary dental care departments were reviewed, 862 patients in Hong Kong and 800 in London. The morphology of the stylohyoid complex was allocated to one of 12 patterns.
Results: A normal styloid process is significantly more prevalent in Hong Kong (P<0.01). A calcified stylohyoid ligament is significantly more common in London (15.8%) than Hong Kong (3.9%, P<0.01), whereas there is no difference in the prevalence of an elongated styloid process (7.8% in London and 8.6% in Hong Kong). Segmentation was significantly more prevalent in London (P<0.01), whereas symmetry predominated in Hong Kong (P<0.01). Although the mean age of the Hong Kong patients was significantly older than those in London (P<0.001), those with a calcified stylohyoid ligament tended only to be older (0.025>P>0.01). There was no significant difference in age for an elongated styloid process.
Conclusion: There are significant differences in the morphology of the stylohyoid complex between London and Hong Kong. A calcified stylohyoid ligament is more prevalent in Londoners.