Teeth that are particularly sensitive when eating acid are often seen as dentin sensitivity, which is commonly associated with excessive tooth wear, gum recession, and wedge-shaped defects. Desensitization or resin filling is needed. 1. Excessive tooth wear. Everyday like to eat hard food or partial chewing, teeth can be excessive abrasion leading to exposure of dentin, can cause pulp reactive pain, for the symptoms of light can use strontium chloride and other drugs to desensitize, the symptoms of serious can be done to protect the teeth with crowns. 2. Gum recession. When periodontitis, alveolar bone resorption gingival recession, root exposure of tooth sensitivity symptoms, at this time the general use of drug desensitization, while periodontal treatment to eliminate periodontal inflammation. 3. Wedge-shaped defects. Wedge-shaped defects need to be filled with resin to isolate the dentin from the outside world, the symptoms will generally disappear slowly, but if the symptoms worsen or even symptoms of endodontitis need to carry out root canal treatment. Teeth eat acid particularly sensitive recommendations to the hospital in a timely manner to avoid aggravation of the symptoms of endodontitis.