Three-year-old baby tooth root surface layer off may be caused by poor oral hygiene, enamel hypoplasia, lack of vitamins, etc., you can pay attention to oral hygiene, dietary modification, vitamin supplementation and other methods to alleviate. 1. bad oral hygiene: with the baby’s intake of food varieties increase, residual food debris in the oral cavity will also increase, do not pay attention to oral hygiene may lead to the baby tooth root surface layer off the situation. Parents can prepare rubber toothbrushes for babies to help babies brush their teeth properly to take care of the oral cavity. 2. Enamel dysplasia: the baby’s daily diet is unreasonable, nutritional deficiency and other conditions will lead to the baby enamel dysplasia, the surface layer of the root of the tooth loss. Parents need to pay attention to the baby’s diet should be balanced nutrition, eat less sweets. 3. Lack of vitamins: baby lack of vitamins or trace elements can also appear tooth root surface layer loss, parents can give the baby moderate eat some vegetables and fruits containing vitamins. If the baby tooth root surface layer loss, parents need to take the baby to the hospital in a timely manner, a clear examination of the root area of the tooth with or without substantial defects, etc., under the guidance of the doctor for the correct treatment.