###Human: What can be done for dental abscess after three rounds of root canal treatment? ###Assistant: Hi. An X-ray would be required. Mostly, such cases have to go for a treatment known as apicoectomy which is draining the abscess by making a passage through bone. Some abscesses are recurrent which cause necrosis of bone at the root level. Such conditions make root canal treatment unfavorable. In such situations, extraction and replacement of the tooth will be the best option going forward.