A mythical person who is said to exist in remote areas of China, but has never been sighted by a reputable source. If existent, he would fix teeth and make them look better. The evidence just simply isn't there to announce he's real.
Mr. Li was excited. He rushed into his home and shouted at his family, "I just saw him! I saw the chinese dentist! He's real, and he gave me a stick with bristles on it!! Behold this magical brush!"