智齿是指人类口腔内牙槽骨上最靠后面的第三颗磨牙,如果从前面正中的门牙往后数,刚好是第八颗牙齿。可以有四颗:右上、左上、左下、右下。但智齿不是人人都有,有些人可以没有智齿,有些则可以有1~4颗智齿。为什么会有智齿的问题?原因是人类进食越来越精细化,导致咀嚼器官越来越退化。具体来说,一方面是牙槽骨出现了退化,牙槽骨变小变短,智齿是 Wisdom tooth refers to the most salient third molars on the alveolar bone in human mouth. If the front teeth of the front of the human body are backward, it is just the eighth tooth. There may be four: upper right, upper left, lower left, lower right. However, not all wisdom teeth, some people may not have wisdom teeth, while others may have 1 to 4 wisdom teeth. Why there is the problem of wisdom teeth? The reason is that humans eat more and more refined, resulting in more and more degradation of the chewing organ. Specifically, on the one hand, the degeneration of alveolar bone, alveolar bone smaller and shorter, wisdom teeth are