Endodontic treatment: what can and what can't be saved.

Although endodontic treatment is generally considered to have a high success rate, not all teeth provide an opportunity for predictable salvage by endodontic therapy and subsequent restoration. New studies are yielding valuable information about factors that affect the outcome of treatment, which enhances the ability of the clinician to make a more accurate preoperative assessment and improve the quality and predictability of treatment. Most teeth can be saved by endodontic treatment; however, some cases fail despite good treatment. How can we assess and predict the outcome of treatment? This paper reviews reasons for biological failure of endodontic treatment and describes clinical factors that influence whether you might treat, refer, or extract the tooth.