The final goal of the research is to understand the origin and racial lineage of the Japanese through clarifying the features of oral cavity of natives in various regions of Japan and neibouring countries. This study describes the dental arch and the palatal traits in Taiwanese males. Ninety-six Taiwanese males, 18 to 24 years old, and 214 Japanese males, as a control, had impressions taken and plaster models made. The measurements were made on the models. The data of Taiwanese males were also compared with those of Taiwanese females, Taiwan aborigonal males, Japanese males (Okinawa and Ishigaki Island), Korean males and Mongolian males. The length and breadth of dental arch, and posterior palatal height in Taiwan males were greater than those in Taiwan females. Dental arch lengths tended to be shorter but dental arch breadths tended to be greater in Taiwanese males than in Japanese males (Okinawa and Ishigaki Island). Dental arch lengths tended to be longer, palatal breadths and lower alveolar breadths in anterior region tended to be greater but those breadth measurements in posterior tended to be smaller in Taiwanese males than in Taiwan aboriginal males. Posterior dental arch length was similar but dental arch breadth tended to be greater in Taiwanese males than in Korean males. Dental arch breadths were similar but dental arch lengths tended to be longer in Taiwanese males than in Mongolian males. The height of the palate tended to be smaller in Taiwanese males than in Japanese males and Taiwan aboriginal males. These findings were similar to the results of studying oral traits in Taiwanese females when compared with other races, and indicated that the morphology of the dental arch and palate in Taiwanese males differed from that of Japanese and Taiwan aboriginal males.
