13 years old does not lose teeth may be in the mouth of the milk teeth have all been replaced, no need to deal with, if the milk teeth have not yet fallen out of the need to observe or extraction. 1. milk teeth have been replaced. 13 years old do not fall out of teeth specifically need to go to the hospital for film examination, some of the milk teeth have been completely replaced, do not need to replace the teeth, do not have to deal with. 2. Milk teeth have not been completely lost. Some 13-year-old milk teeth have not been replaced may be under the milk teeth without permanent teeth embryo, resulting in milk teeth stagnation, if the milk teeth can continue to use can be retained without treatment, can not continue to use, you need to pull out after the denture repair. If there is a permanent tooth embryo may also be affected by genetic or environmental factors, the replacement time is a little late can be observed first, after observation is still not out of the need for artificial intervention extraction. 13 years old does not lose teeth specific recommendations to the hospital to check the oral situation and take X-ray to deal with.