Repairing a cavity usually takes about half an hour to an hour, depending on the shape and condition of the cavity and the skill of the operator. Tooth decay actually refers to the occurrence of dental caries, which is slow and undetectable, and can lead to delayed treatment as the caries progresses to cavity-like changes. The traditional way of repairing cavities is to use silver amalgam, which requires the preparation of a strict cavity shape, so it takes a long time to fill the tooth, usually about an hour. Nowadays, resin or glass ionomer filling materials are often used, which do not require the preparation of a strict cavity shape and cementation shape, so the time spent is shorter, usually taking about half an hour.