Not everyone has wisdom teeth. Wisdom teeth, also known as third molars, usually begin to erupt around the age of 18, but not everyone has wisdom teeth, and it is normal that some people may not grow them for the rest of their lives. The normal number of permanent teeth is 28-32, which means there are 4 wisdom teeth. In the past, because food was hard and difficult to chew, many strong teeth were needed. However, with the refinement of food, there was no need for too many strong teeth and the 4 wisdom teeth started to be phased out, i.e. evolution. In the process of evolution, each person evolves at a different rate, some people quickly evolve all 4 wisdom teeth recede, then no more wisdom teeth erupt, but some people will still grow 1-4. Therefore, wisdom teeth do not necessarily grow in everyone, and the number of wisdom teeth grows in each person is not fixed, but is normal. To determine if wisdom teeth are growing, an x-ray is needed to see if there are wisdom teeth growing, because even if they are not exposed in the mouth, they may be buried in the bone.