People who have difficulty breathing through their nose may develop a low-grade, chronic gingivitis on the visible side of the upper front teeth. The tissues may fill with fluid and bleed easily on light stimulation. It may be caused by an increase in the number of aerobic bacteria, which thrive because of the continuous exposure to air. It may also be due to prolonged periods of dry gums. The condition can be frustrating if excellent oral hygiene does not fully alleviate the problem. Dental procedures can be difficult for mouth breathers to tolerate. Use of external nasal dilators for such patients may prove helpful.