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.
