Interappointment pain: mechanisms, diagnosis, and treatment

Abstract

Knowledge on the causes of and the mechanisms behind interappointment pain in endodontics is of utmost importance for the clinician to properly prevent or manage this undesirable condition. The causative factors of interappointment pain encompass mechanical, chemical, and/or microbial injury to the pulp or periradicular tissues, which are induced or exacerbated during root canal treatment. Microorganisms can participate in causation of interappointment pain in the following situations: apical extrusion of debris; incomplete instrumentation leading to changes in the endodontic microbiota or in environmental conditions; and secondary intraradicular infections. Interappointment pain is almost exclusively due to the development of acute inflammation at the periradicular tissues in response to an increase in the intensity of injury coming from the root canal system. When an interappointment emergency occurs, proper diagnosis and active treatment are required for the clinician to succeed in solving the problem. This review focuses on the mechanisms of interappointment pain, with special emphasis placed on the causative agents and the host response to injury that can precipitate pain. In addition, diagnostic measures and treatment approaches to manage interappointment pain are also discussed.

Clinical strategies for managing emergency endodontic pain

“…The diagnosis should be the starting point for pain control, because the pain cause may involve anatomic and psycho factors [19,37]. The first D consists of establishing the differential diagnosis based on identifying oral pathologies and their origins through step-guided investigation, obtaining objective and subjective information on the problem.…”

“…In these cases, the exudation is confined to the apical area and the drainage is obtained through the total instrumentation of the canal with the foramen trepanation attempting to drain the pus through the canal [37]. The intraoral presence of the pus localized at the vestibule bottom (fluctuating, nonfluctuating, localized or diffuse), requires surgical drainage due to the pus in the subperiosteal/ submucosal area.…”

“…Flare-up or post-operative pain is the emergency care between endodontic appointments of root canal preparation. It is characterized by pain, swelling, or both [18,37]. Many articles report the prevalence of post-operative pain, ranging from 1.4% to 16%, as well as flare-up causes, such as the use of different intracanal medications, irrigant solution, instrumentation techniques, and number of appointments [5,18,29,37].…”

“…According to Siqueira and Barnett [37], the factors causing pain during endodontic procedures are of chemical or mechanical origin and commonly associated to iatrogeny, microbial factors present in pulp and periradicular pulp, and presence of periapical lesion induced or aggravated during root canal treatment [37]. The microorganisms may cause pain in between appointments due to the following situations: apical extrusion of debris, incomplete instrumentation leading to alterations in the endodontic microbiota, and secondary intraradicular infections [29].…”

“…The mild pain after chemical-mechanical preparation may occur in approximately 10-30% of the cases, and in most cases, the discomfort is decreased with common analgesic drugs to relieve the symptoms [5]. The development of moderate to severe post-operative pain, with or without swelling, on the other hand, ins uncommon and demands emergency care [37].…”