Is tooth root abscess nerve alive?

If the tooth has a root abscess, most of the cases in the root is no live nerve, nerve is already necrotic. If the tooth has a root canal abscess, we basically will not show pain because of the live nerve when we open the pulp, so at this time if the pulp can be opened without local anesthesia. Without local anesthesia, there will be no obvious pain reaction in the pulp. And in the root irrigation, in the preparation of the root, in the root filling time will not show pain reaction. Tooth root abscess may be due to pulpal inflammation did not clean in time, did not do treatment in time, so the development of root abscess caused by the root tip, under normal circumstances, the root canal inside the pulp has been necrotic.