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.
There is no one treatment that will be right for all causes of a bleeding tooth. Instead, your care will need to be customized to suit your specific problems. There are some cases where a bleeding tooth will be the result of a trauma. The trauma could be dental work or an injury caused by being hit in mouth area. If the cause of the bleeding is dental work, keep in mind that such bleeding should not continue for more than a day.