Gingivitis is a common gum disease caused by a buildup of plaque and tartar. It causes swelling, aching and bleeding of the gums. Smoking significantly increases the risk of developing gum disease. To treat gingivitis, one should schedule a professional dental cleaning to remove built up grime, brush teeth twice a day, floss daily, and use mouthwash at a different time than brushing. Maintaining good oral hygiene practices can lead to healthier gums.