A middle-aged dog developed a swelling on his face. It did not go away after 2 weeks of antibiotics. His teeth had tartar and were difficult to look at well without sedation. The next step is to figure out what is causing the swelling. A tooth root abscess? Or a tumor? Here is a picture of the face swelling: We anesthetized him to better assess the swelling. First we put a needle in the swelling and drew out some material. It looked like it could be an infection. One of the teeth under the swelling was broken. Maybe that was the cause? But the x-ray of the tooth was normal. Here is the normal x-ray: A tooth root abscess looks like a halo around the root. There is a picture of one in an earlier blog. But his tooth was broken and the inside of the tooth was exposed. We removed the tooth, drained and flushed the swelling and it resolved. While x-rays are an important part of a dental treatment to find disease that you cannot appreciate externally. A good exam of each tooth under anesthesia is also a critical part of the dental treatment.