A cleaning makes your teeth and fillings smooth, so it's harder for plaque to build up on your teeth. Plaque is clear and sticky. It forms on your teeth every day. If plaque is left on your teeth, it hardens into tartar (also called calculus). A cleaning is the only way to remove tartar. It cannot be removed with your toothbrush. If tartar is not removed, it can cause gum disease. A cleaning also removes some stains, so your teeth look brighter. Here are the main steps in a cleaning. Your dentist or dental hygienist may do these steps in a different order, because your teeth are unique.