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.
Dry socket is also known as alveolar osteitis and happens where a blood clot fails to develop in the tooth socket as a normal part of healing, or if the blood clot is dislodged. Dry socket can cause an aching, throbbing pain in the gum or jaw. There may also be a bad smell or taste coming from the tooth socket.