Pain after filling may be a manifestation of transient irritation, pulpitis, apical periodontitis, which requires refilling or root canal treatment. 1. Transient pain: the pain of hot and cold stimulation occurs in a short period of time after filling, but the pain disappears immediately after the stimulation is removed, it may be the manifestation of reversible pulpitis, and it is recommended to remove the filling material, and then refill the filling after being cushioned. 2. Delayed pain after stimulation: mainly manifested as pain after hot and cold stimulation, and delayed for a period of time after the stimulation is removed, ranging from a few minutes to a few hours, it usually manifests that the pulp has been irreducible to inflammation, and root canal treatment is needed. 3. Biting pain: common in the filling after a period of time or after root canal treatment, the former need root canal treatment, the latter need root canal re-treatment. It is recommended that patients who feel uncomfortable after filling can go to the hospital to avoid delaying their condition.