Adult tooth decay should take the following treatment methods: 1.When the front tooth decay occurs, the healthy tooth structure can be preserved as much as possible, and the composite resin with similar color to the tooth is used for filling; when the cavity exists in the back tooth, it is better to use the silver amalgam with stronger pressure resistance for filling, and the filling can be made inlay bonding restoration when it is easy to fall off; 2.If the cavity is deeper and close to the pulp, the cavity should be prepared in the process of avoiding If the cavity is deep and close to the pulp, accidental pulp penetration should be avoided during the preparation of the cavity, and pulp protector such as calcium hydroxide should be placed at the bottom of the cavity to reduce the irritation to the tooth; 3.If the pulp is exposed in the cavity and causes severe pain, the pulp should be removed under local anesthesia to complete the root canal treatment, and metal or all-ceramic crown should be made to avoid the tooth from splitting.