Teeth soft after eating acid may be dentin allergy, caries and so on, according to the situation to choose desensitization treatment, filling and restoration and other treatment methods. 1. Desensitization treatment: teeth soft after eating acid caused by dentin allergy, you can choose anti-allergy toothpaste to brush teeth, and at the same time the application of desensitizing agents for desensitization treatment, commonly used desensitizing agents are sodium fluoride, silver ammonia fluoride and so on. 2. Filling and restoration: tooth decay reaches the superficial layer of dentin, there will be a soft tooth after eating acid, this situation needs to clean up the decayed tooth tissue, and then filling and restoration. After the tooth is filled, maintain good oral hygiene, eat less sweets, drink less carbonated beverages, etc., to prevent caries in other teeth. Teeth eat acid soft timely to the hospital, clear cause of the disease after active treatment to prevent further development of the disease.