Is it possible to have a abcess where a tooth was extracted a year ago? The reason I ask is because I have has swollen lymph node for about nine months, just last month it enlarged to 3 centimeters. My ENT has just removed three swollen lymph nodes. But

Make an appointment. Swollen lymph nodes, while they can be related to something as simple as a common cold, can also be signs of life-threatening conditions. You can evaluate any dental components at a routine 6 month dental exam, but if something is hurting, swelling or bleeding you have an instability and it's time for an intervention. Be serious. Make an appointment with your dentist and your ENT.
Biopsy of the node. If the node remains enlarged (greater than 10mm) for3 months, or continues to grow, biopsy of the lymph node is indicated with CBCd blood test.