A student who wishes to treat diseases of the mouth may wish to study dentistry. Dentistry studies how to keep the teeth, gums, and other parts of the mouth healthy and how these parts interact with the body.

Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south.