Plaque is a sticky white film of bacteria that accumulates on your teeth about every 24 hours. If thorough plaque removal isn’t achieved, carbohydrates and sugary foods mix with the plaque to form acid. This acid begins to destroy the outer layer of the tooth for 20 minutes or so starting a cavity. If plaque is allowed to accumulate on the teeth, it eventually hardens into tarter or calculus. Once calculus forms, it must be professionally removed.