Aim: The aim of this study was to evaluate the effect of chlorhexidine (CHX) irrigation on the root dentin microhardness of single rooted teeth compared to saline irrigation before the application of double antibiotic paste (DAP) for two weeks in regenerative endodontics.
Subjects and methods: Thirty-two single rooted teeth were selected. Following decoronation and mechanical preparation, teeth were randomly assigned into two groups in accordance with irrigation technique as follows: the intervention group; irrigation with 20 ml of 1.5% sodium hypochlorite (NaOCl) then irrigation with 20 ml of saline followed by irrigation with 2% CHX, while the control group; irrigation with 20 ml of 1.5% NaOCl then irrigation with 20 ml of saline. After treatment; 1 mg/ml of DAP was injected to canal system for two weeks. Pre-treatment dentin microhardness was measured for a 2mm cervical cut before the irrigation protocol. Post-treatment dentin microhardness was measured for remaining root section. Microhardness was measured by vickers test machine.
Results: the microhardness value before treatment was significantly higher than after treatment in both groups. However, there was no statistically significant difference in microhardness values between intervention and control groups after treatment.
Conclusion: Within the study limitation, 2% CHX irrigation did not decrease the root dentin microhardness.