Normal Saline or Sodium Hypochlorite Irrigation for Vital Pulp Therapy? A Non-Inferiority Randomised Controlled Trial

Objective: To compare treatment success and discolouration of the permanent posterior teeth treated with vital pulp therapy (VPT) using mineral trioxide aggregate (MTA), irrigated with sodium hypochlorite (NaOCl) or normal saline solution.
Methods: A randomised non-inferiority trial was conducted. One hundred and twenty-five teeth that met the inclusion criteria were randomised to each irrigant, 65 in the NaOCl and 60 in the NSS groups. ProRoot® MTA was used as a pulp dressing material in both groups and teeth were followed for 12 months. The pri-mary outcome was the success of VPT; requiring both clinical and radiographic success to be considered as success. The hypothesis of the primary outcome of this study was that the absolute difference of VPT success in the NSS group was not worse than that in the NaOCl group, by a margin of 5%. The hypothesis of the secondary outcome was that the NSS group would have a lower percentage of discolouration com-pared to the NaOCl group.
Results: Using a per protocol analysis, the absolute difference of VPT success between the NSS and NaOCl groups was 2.08% (95% CI: -1.95, 6.1). Perceptible grey discolourations were 80% and 63% in NaOCl and NSS groups (difference -17%; 95% CI: -40.0, 6.2; p=0.15).
Conclusion: For MTA-VPT procedure, irrigation with NSS was not worse than that with NaOCl. However, NSS did not lower the percentage of discolouration as discolouration was found in both irrigant groups.