Your teeth are covered in a sticky film known as dental plaque. This plaque contains hundreds of different species of bacteria responsible for both gum disease and tooth decay. If plaque is not removed on a regular basis, it can harden into calculus. You cannot get rid of calculus with your tooth-brush, we have to get rid of it with our special instruments. If calculus is not removed by the dental practitioners, it attracts more plaque due to its rough surface as such increases your risk for developing gum disease and tooth decay. Furthermore, gum disease has been linked to other systemic conditions such as heart attack, stroke, diabetes etc. Therefore, having your teeth cleaned professionally twice a year can also lower your chances of developing other systemic conditions.