Endodontics is a dental term used for "root-canal treatment". Endodontics can help you keep your natural teeth by removing the tooth's pulp, a small thread-like tissue, which was important for tooth development. Once removed, it is replaced with materials that seal off the root canal. Years ago, diseased or injured teeth were often extracted. Today, even if the pulp of one of your teeth becomes injured or infected, it often can be saved through root-canal (endodontic) treatment.