Comparison of post-operative pain in relation to working length assessment by electronic apex locator and digital radiography in permanent teeth among pediatric patients

Background: Effective measurement of working length is essential for successful endodontic treatment. Electronic Apex Locators (EAL) and Digital Radiography (DR) are commonly used methods, yet their comparative impact on post-operative pain remains unclear. This study aimed to compare post-operative pain intensity and pain dissipation duration following working length determination using EAL and DR in pediatric endodontic patients. Methods: A total of 130 patients aged 10–15 years were randomly assigned to the EAL group (n = 65) or the DR group (n = 65). Pain intensity was assessed using the Visual Analogue Scale (VAS) at pre-operative, and at 6, 12, 24, 48 hours, and 7 days post-operatively. Pain scores were further analyzed by age and gender. Independent and paired t-tests and Analysis of Variance were applied for statistical analysis. Results: No statistically significant difference was observed between the EAL and DR groups in VAS scores at any time point (p > 0.05). Female participants consistently reported higher mean pre- and post-operative pain scores compared with males, with significant differences observed in both groups (EAL: p = 0.031; DR: p < 0.001 for pre-op scores). Overall, while both groups showed comparable pain reduction trends over time, gender influenced pain perception and pain relief duration significantly in both treatment modalities. Conclusions: Both EAL and DR are effective for working length determination, showing no significant difference in post-operative pain. Pain perception and relief duration, however, vary with gender and age and should be considered during endodontic treatment planning. Clinical Trial Registration: The trial was retrospectively registered with ClinicalTrials.gov (Identifier: NCT07181252, Retrospective registration).

Post-operative pain; Working length; Radiography

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