Cavity filling is a dental procedure used to treat tooth decay. When a cavity forms, it creates a hole in the tooth that can lead to pain and further damage if not addressed. During the filling process, a dentist removes the decayed part of the tooth and cleans the area before filling it with a material such as composite resin, amalgam, or glass ionomer. The filling restores the tooth's shape and function, preventing bacteria from entering the cavity. After the procedure, patients may experience some sensitivity, but this usually subsides quickly. Regular dental check-ups can help prevent cavities and maintain oral health.