Influence of preoperative pain intensity on postoperative pain after root canal treatment: A prospective clinical study

Objectives: The aim of this prospective study was to investigate the correlation between the intensity of preoperative pain and the presence of postoperative pain, taking into account the variables sex, tooth type, arch, and tooth vitality. Methods: Two hundred and seventy patients with pulpal pathology who were scheduled for routine endodontic treatment were enrolled in this study. Conventional endodontic treatment was carried out in a single visit. The chemomechanical preparation of root canals was performed with ProTaper instruments, and canals were obturated with a warm gutta-percha obturation technique. A structured questionnaire was used to record data on sex, age, type of tooth, location and pulp diagnosis. Patients were asked to record their preoperative and postoperative pain using a 10-cm visual analogue scale (VAS). Postoperative pain and the need for analgesic consumption were assessed at 4, 8, 16, 24, 48 and 72 h post-treatment. The data were analyzed using the Mann-Whitney U and chi-square test, and the significance was set at P < .05. Results: The mean level of pain after root canal treatment was 2.58 +/- 2.80 on a VAS between 0 and 10. Variables that were associated with a higher preoperative pain intensity (female, mandible and molar) also had a higher value of postoperative pain (P > .05). Conclusions: Within the limitations of this study, it can be concluded that the presence of preoperative pain is the variable that most influences the prevalence of postoperative pain. Clinical significance: Pain management should be an integral part of dental treatment. The present study analyses the incidence of postoperative pain that should be expected by patients with different intensity of pain before root canal treatment. (C) 2015 Elsevier Ltd. All rights reserved.