Why does a tooth smell after a filling?

After a dental filling, if an unpleasant odor develops from the tooth, it may be due to oxidation of the filling or lining materials over time. In the initial period following the procedure—especially within the first 2–3 days—some slight odor in the mouth is normal and commonly occurs. However, if the bad odor persists for an extended period after the filling, this may indicate an abnormal condition. Persistent odor could be caused by periodontitis or other oral diseases. When such problems occur, it is recommended to visit a hospital for a thorough examination to identify the underlying cause of the odor, followed by appropriate treatment as advised by the dentist. Maintaining good oral hygiene is also crucial, including eating foods beneficial for oral health such as vegetables and seaweed, and rinsing the mouth after every meal to help alleviate oral issues.