This is the last, but extremely important step in preventive dentistry and tooth cleaning. It involves finishing the surface of the teeth to make them shiny and clean. There are two kinds of polishing: air polishing and rubber tip polishing. Air polishing works by spraying high pressured water mixed with baking soda paste onto the surface of your teeth. This powered water washes away residue and plaque while baking soda removes stains. Rubber cup polishing uses a low-speed and gentle hand piece that contains a polishing paste made of abrasive ingredients ideal for removing stains. The main reason for this preventive dentistry technique is that smooth the tooth surface makes it difficult for plaque to build up on it.