Dental fillings are divided into five major steps: preoperative preparation, cavity preparation, moisture barrier drying, filling and polishing. 1. Pre-operative preparation: The depth of dental caries is assessed through clinical examination and dental radiographs before the operation, and the consumables and equipment used are prepared, and rubber barriers are put on in advance in hospitals that are in a position to do so. 2. Cavity preparation: After preoperative preparation, the dental handpiece is used to grind away the decayed tissue, and according to the patient’s intraoperative response and the depth of decay, the choice is whether to grind away the caries completely or to leave some soft caries at the bottom, with the possibility of retaining the living pulp. 3. Moisture barrier drying: equipment such as cotton balls and rubber barriers are used to make the area around the tooth as dry as possible and blow dry it slightly. 4. Filling: Apply bonding agent, and then fill in composite resin or glass ionomer filling material in layers, some deeper caries cavities, calcium hydroxide material needs to be cushioned to protect the pulp before filling. 5. Polishing: After filling, adjust the bite and polish the tooth surface to prolong the service life as much as possible. It is recommended that patients with dental caries go to the stomatology department of regular hospitals as soon as possible to avoid delaying the condition and causing pulpitis and apical periodontitis.