Post-endodontic Flare-ups after a Single-visit Treatment Using the FUI Scoring Method and Associated Factors: A Clinical Prospective Study

Abstract

Flare-ups following a root canal treatment are still a major problem both to the patient and to the clinician. Its definition, etiology, incidence, and risk factors have been the subject of long-standing debate. We conducted this study to investigate the incidence of flare-ups after a single-visit treatment and to identify the factors associated with the flare-up index (FUI). All patients treated by postgraduate residents in endodontic specialty at Saint Joseph University of Beirut from June 2018 to January 2019 were invited to participate in the study. After a routine root canal treatment, patients were given a questionnaire to fill after 24 hours-48 hours-7 days, covering a postoperative assessment of symptoms using the visual analogue scale (VAS) and FUI. Patients who experienced a severe postoperative pain and/or swelling were identified and categorized as having a flare-up. A total of 423 patients (age: 39.76 ± 12.428 years) were included in the study. The incidence of flare-up was 1.9%. The mean FUI was 5.94 ± 5.646 and was highly correlated with the VAS score (p < 0.001). The factors that significantly influenced the occurrence of flare-ups were: pulpal diagnosis (p < 0.001), preoperative drug intake (p < 0.001), preoperative symptoms (>24 hours) before treatment (p < 0.001), and tooth type (p = 0.013). FUI should be used in further studies to confirm our results since it is a valid quantitative method to assess this clinical phenomenon. Endodontists should take into consideration the diagnosis and the history of preoperative symptoms since it plays an important role in predicting the occurrence of flare-ups and the success of the treatment.