If a tooth is hollow and painful, it is necessary to actively consult a doctor for treatment. Depending on the situation, filling treatment, root canal treatment and extraction of the affected tooth will be carried out respectively. 1. Filling treatment: If the cavity is not deep and has not invaded the pulpal tissue, that is, the nerve, it is enough to directly consult the doctor for filling treatment, and the main steps are: cavity preparation, rinsing and disinfecting, applying adhesive, composite resin and other filling materials to fill the cavity. 2. Root canal treatment: If the cavity is deeper and has already invaded the pulp tissue, at this time, the patient is often accompanied by obvious symptoms such as spontaneous pain, night pain, etc., and needs to actively seek medical treatment for root canal treatment, the main steps are: root canal preparation, root canal disinfection, root canal filling, and pay attention to the crown as soon as possible for restoration. 3. Extraction: If the bad tooth is very deep or large, and the remaining tooth tissue has no preservation value, then you need to actively seek medical treatment for extraction, and pay attention to the fact that you can’t brush your teeth or rinse your mouth within 24 hours after extraction. Specific treatment should be determined under the guidance of the doctor according to the condition.