Most of us think of the dentist's office when we hear about plaque, but plaque doesn't just form on our teeth. It can also form inside the arteries. These are the blood vessels that carry oxygen and blood to the heart, brain and other parts of the body.
Arteries have an inner layer of muscle and when it is damaged, plaque can form. Something causes the layer's cells to mutate and they begin reproducing much more rapidly. This creates a bulge inside the arterial wall.
Technically, these bulges are tiny, benign tumors, but they can grow big enough to cause the inner lining of the artery to rupture. When this happens, the blood brings clotting fibers called fibrin to patch the tear. Minerals, especially calcium, get become trapped in the fibrin net, along with fats like cholesterol. As more and more debris builds up over the site, the arteries narrow, reducing the flow of blood through them. They can also become clogged, stopping blood flow completely.
This condition is known as atherosclerosis. The part of the body that is affected by the condition depends on which arteries have plaque. When the arteries to the heart become clogged, the result is angina (chest pain) or a heart attack. If arteries in the legs are affected, it can lead to pain in the legs, particularly when you are walking. Hardening of the arteries to the brain can cause strokes.