A study done at the University of Connecticut at Farmington with 120 participants was split into two groups, half receiving regular tooth cleaning, and half undergoing extensive dental work like scaling, root planning, antibiotics, and even removing diseased teeth. After 6 months the group that underwent intensive dental work had healthier arteries.
Dr. Maurizio S. Tonetti, said "This study showed that intensive treatment of periodontitis, a common potential source of low-grade inflammation, results in an improvement in endothelial function." In other words, it makes the arties cleaner and more flexible, allowing the blood to flow freely and preventing clotting. The connection between the heart and the mouth isn't all that clear, but it may have to do with bacteria.
Another study done at Columbia University found a relationship between bacteria in the mouth and carotid artery health. Keep your mouth clean and your smile bright, and see a dentist if there is a problem. In addition to helping your smile it may help bring a smile to your heart.