Philpott R, et al. - Authors gauged the prevalence, pain catastrophizing and other predictive factors, and clinical course of persistent pain/discomfort related to the teeth displaying periapical healing following non-surgical root canal treatment (NSRCT). In most cases, a decrease in the persistent pain or discomfort associated with teeth showing periapical healing at the first review after NSRCT over the following 6-months was seen. In the majority of those with a confirmed radiographic absence of periapical disease, spontaneous improvement or symptom resolution was revealed in longer-term follow-up. They identified five predictive factors (history of chronic pain, teeth with responsive pulps, association with pain, diagnosis of tooth-crack before treatment, and diameter of pre-operative radiolucency).