There are numerous conditions that a cardiologist treats. These include repair or replacement of heart valves; bypassing or widening of blocked arteries to the heart; repair of aneurysms; treatment of coronary artery disease to name a few.
Flossing reduces the number of bacteria in the mouth. The same bacteria can cause multiple dental problems. So, in order to keep the mouth free from any dental issues, you must floss along with brushing.