Your now long tooth is known as wisdom tooth, usually the tooth that grows after 18 years old. Human in the process of evolution as the food is more and more sophisticated, jaw bear the burden of the corresponding reduction, lead to jaw bone mass, but the volume is not less teeth, eventually make the position of the teeth eruption is insufficient, because food scraps, oral bacteria breeding is easy to form a wisdom tooth pericoronitis, so in the long wisdom tooth, I will keep the mouth clean, often with warm salt water gargle.
The origin of wisdom teeth: wisdom teeth refers to the four third molars in the human mouth, the top and bottom of the alveolar bone. Because this 4 third molars were just began to appear in 20 s, close to human physiological and psychological development mature at this time, and was seen as the symbol of "wisdom", so called it "wisdom teeth" -- wisdom tooth.
