Drinking hot water toothache has the following reasons: 1, consider whether it is accompanied by night pain, spontaneous pain, etc. If there is spontaneous pain at night, the pain of drinking hot water, drinking cold water to relieve, it should be pulp inflammation, need to root canal treatment, i.e. nerve killing treatment; if there is no spontaneous pain at night, pain when drinking hot water, but the pain is quickly relieved after the hot water is removed, it may be caused by decay, need to remove the decayed tooth tissue 2.Dentin allergy caused by tooth abrasion, wedge-shaped defect caused by lateral brushing, hidden tooth fracture caused by biting hard objects, etc. may also occur, and need to go to dentistry for further treatment, dentin sensitivity can be solved by desensitization treatment; wedge-shaped defect can be filled directly if the pulp is not damaged; hidden tooth fracture needs to make a crown to wrap up the tooth to prevent further deterioration of the hidden fracture and lead to tooth splitting. Cryptoconus requires a crown to encase the tooth to prevent further deterioration of the cryptoconus leading to tooth fracture.