This includes general external causes of pigment teeth (coffee, tea stains, smoke stains deposition), moderate tetracycline stained teeth, dental fluorosis, drug-discolored teeth, hereditary Huang Ya.

• 这包括一般外因性色素牙(咖啡、茶渍、烟渍沉积)、中度四环素牙、氟斑牙、药物性变色牙、遗传性黄牙。