Using a toothbrush and dental floss, the player must keep the teeth clean while avoiding contact with the Plaque Germ, known as "D.K". If D.K. comes into contact with the player, this will result in loss of one life. The brush needs tooth paste to work so the player must apply tooth paste. Floss is used for the space between teeth. If the teeth aren't cleaned properly and start to decay a warning bell sounds. Eventually the tooth will disappear, reflecting tooth loss. If a tooth is completely cleaned, a brief musical score will play and the teeth will change colors repeatedly. If the player comes into contact with D.K. at this time, the Plaque Germ will disappear for a time. Losing all lives or having four teeth lost will end the game.