Several irrigation techniques have been recently introduced with the main objective of improving root canal disinfection. This in vitro study aimed at comparing the post-operative pain after the use of two different irrigation tips: a side-vented needle and an end-vented needle in one-visit root canal treatment. Methods: thirty patients with Symptomatic irreversible pulpitis were divided randomly in two groups, Group A: Max-i-Probe;Group B: NaviTip. Afterobturation.Pain assessment was done pre-operatively, 4, 12, 24, 48 hours post-operatively using the modified Visual Analogue Scale (VAS). Results: showed that the side-vented needle showed similar effect on post-operative pain as end-vented needle.