A filled tooth can be refilled. A filled tooth needs to be refilled, mostly because of the following situations: in the first case, the material of the filling is dislodged; in the second case, secondary caries. A filled tooth may lose material and need to be refilled in a timely manner. This may occur because the filling is not tight enough, resulting in a gap between the filling material and the tooth, or the filling material is overhanging. After the filling material is dislodged, it is important to go to the dentist for refilling as soon as possible. If there are food residues remaining in the cavity for a long time, it is likely to induce pulpitis. If secondary caries occurs, the cavity should be filled again after removing the original filling and the secondary infected tooth. If caries occurs in other parts of the tooth, it is necessary to consult a doctor in time, because the tooth has lost its ability to resist infection at this time, and if the caries is not treated, the cavity will gradually become larger. After repairing the tooth, you need to pay attention to good oral hygiene, and if you find any abnormalities, you should be treated as soon as possible.