The ductus arteriosus is a hole that allows the blood to skip the circulation to the lungs. However, when the baby is born, the blood must receive oxygen in the lungs and this hole is supposed to close. If the ductus arteriosus is still open (or patent) the blood may skip this necessary step of circulation. The open hole is called the patent ductus arteriosus.
Caring for a Bleeding Tooth. Some people mistakenly think that while brushing, a bleeding tooth is perfectly normal. It is not. Anytime there is any bleeding in the mouth, it is almost always a sign of periodontal disease. Even if you brush fairly hard, it should not cause healthy teeth and gums to bleed.
Bleeding gums can be a sign that you have or are at risk for gum disease. Ongoing gum bleeding may be due to serious medical conditions such as leukemia and bleeding and platelet disorders. The main cause of bleeding gum is the buildup of plaque at the gum line. This will lead to a condition called gingivitis, or inflamed gums. Plaque that is not removed will harden into tartar. This will lead to increased bleeding and a more advanced form of gum and jawbone disease known as periodontitis.