婴儿刚出生时,口腔内没有牙齿。但口内环境有利于致病能力及存活繁殖率低的需氧菌生长。当牙齿萌出以后,由于牙齿的邻面、龈沟,牙齿咬合面凹凸不平窝沟的出现,使口内环境又有利于致病能力及存活繁殖率高的厌氧菌生长。因为在微生物中,大约有三 When a baby is born, there is no teeth in the mouth. However, the oral environment is conducive to pathogenic capacity and survival of low reproductive growth of aerobic bacteria. When the teeth after eruption, due to the teeth of the adjacent surface, gingival sulcus, occlusal surface occlusal indentation fissure appears, so that the oral environment is conducive to pathogenic capacity and survival of anaerobic bacteria growth rate high growth. Because in microbes, there are about three