Cavities can easily cause bad breath. If there are cavities, food will remain in the holes of the cavities, get stuck, and ultimately compress the gums, and it will be difficult to clean. Foods are prone to ferment and produce acids causing bad odors, and the gums can also become inflamed, and even suppurate, which also produces bad smells. Therefore, if you have cavities, you should go to a regular hospital's dental department and receive targeted treatment under the guidance of a dentist. It is essential to develop good oral hygiene habits, brush your teeth in the morning and evening using the internationally recognized Bass brushing technique, rinse your mouth after meals, learn to use dental floss to remove food residues in tooth gaps, and treat cavities promptly to prevent them from deepening and causing more severe consequences.