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.
Dear Jessica, The percentage of people whose gums occasionally bleed when they brush is actually quite high â as much as 90% of the population, in fact. Bleeding gums is generally a sign that your gums are inflamed, and that you are not brushing and/or flossing optimally. The instrument that your dentist, hygienist or periodontist (gum specialist) uses to investigate and determine whether or not you have periodontal disease is called, aptly, a periodontal probe.