Patient: had a lot of cavities, all filled, but the innermost two of the upper teeth are decayed out (there are two other wisdom teeth inside these two that are fine), only the roots are left, and they have not been extracted. No matter how hard I brush my teeth, the other teeth still have plaque and are close to decaying The previous fillings are fine Should I pull the two teeth that are decayed? Will the other teeth come loose? I heard that fluoride coating can prevent cavities, is it okay? If not, is there any medicine that can prevent cavities? Why are my teeth so prone to decay? What should I do? Han Yongcheng, Department of Preventive Stomatology, Beijing Stomatological Hospital: If two teeth have been decayed, you should go to the hospital to see if the roots can be preserved. If the roots can be preserved, try to treat the roots so that they can be utilized to attach a tooth. If the root is so bad that it cannot be preserved, it should be extracted without having to cause inflammation of the root tip due to root infection. After the wound has completely grown back, dentures are placed to restore chewing function. There are two main ways to prevent dental caries (tooth decay), one is to use fluoride toothpaste to brush your teeth, or twice a year with fluoride coated on the teeth, the other is to use the method of socket closure, that is, in the parts that are easy to be damaged by decay (on the surface of the chewing food) with a polymer resin material will be those deep sockets enough to be closed, so that you can greatly reduce the chance of tooth decay. Patient: Thank you very much doctor, I would like to trouble you again, may I ask the fluoride coating, is it available in the drugstore? What brand is good? Can I apply it at home? For people like me who have had many fillings, can I have my teeth cleaned? Will the fillings be washed off? I used to have two porcelain braces for 6 years, do I need to have them redone? How can I tell when my porcelain teeth are no longer usable? What is the life expectancy of porcelain braces? Han Yongcheng, Department of Stomatology, Beijing Stomatological Hospital: 1. At present, fluoride foam is not sold in pharmacies, and it needs to be used by doctors in specialized dental hospitals. The same needs to be used if the teeth have been filled. In order to prevent new caries and fillings over the formation of secondary caries, especially children who are doing orthodontics, should be used every three months. 2. Porcelain crowns do not need to be redone if there are no problems. Its service life is different, according to the quality of doing and their own use, the time varies greatly. Patient: Hello doctor, probably due to genetic reasons, my baby is only three weeks old this year, there are four or five cavities, that is, the upper large incisors and the two teeth next to them, all have small cavities. We went to our local doctor here and he said that she was born with bad enamel that is chalky and especially prone to cavities, but it’s not a good time to fill them, they’re too small. She needs to wait for a new tooth. May I ask the doctor, is it a good idea? After all, the child is too small, waiting for the replacement of teeth, there may still be several years, we are afraid that by that time has been decayed, affecting the germination of permanent teeth. How to protect the baby’s teeth, how to make the baby’s permanent teeth can sprout neat and healthy? Han Yongcheng, Department of Stomatology and Preventive Medicine, Beijing Stomatological Hospital: Hello, if your baby has more caries in the mouth, it means that he or she is a caries-prone child, so it is recommended that you take him or her to the pediatrics or preventive medicine department of the stomatological hospital, and undergo topical fluoride anti-caries measures. For example, fluoride foam every 4 months.