The root of the tooth is exposed for the following reasons: 1, caused by periodontal disease, generally due to poor oral hygiene, dental calculus stimulates the gums, resulting in bleeding gums, gum recession, will lead to the root of the tooth exposed in the mouth, generally need to carry out periodontal scaling, and do subgingival scaling, maintenance of periodontal health, can avoid the phenomenon of gum recession again, the root of the tooth exposed symptoms will not develop again. 2, it may be caused by improper brushing, such as brushing horizontally or using a toothbrush with hard bristles, which can cause gingival recession and root exposure; there may also be a wedge-shaped defect in the teeth, generally correct the brushing method, and resin repair can be carried out for those who have already had a defect, and it is necessary to maintain good oral hygiene and try to use a soft-bristled toothbrush with a small head in order to avoid the phenomenon. It is necessary to maintain good oral hygiene and use a soft-bristled toothbrush with a small head in order to avoid damaging the gums.