Objective: evaluate the solubility, pH, antimicrobial activity, and cytotoxicity of N-Acetylcistein (NAC), Ambroxol hydrochloride (AMB), and Calcium Hydroxide (CHP). Methods: Solubility was determined by the volume obtained, by microCT, before and after immersion in water for 7 days. For pH, acrylic tubes containing the pastes were immersed in ultrapure water, and Ph was measured at time-intervals of 3 h, 3 and 7 days. Antimicrobial activity was analyzed by the percentage of living cells using the Live and Death method with confocal microscopy. Cytotoxicity was tested with Fibroblast-like cells L929, and cell viability was evaluated at time-intervals of 6, 24 and 48h. Data were statistically compared (P=5%). Results: Solubility values were the highest for NAC, and lowest, for CHP. Pastes NAC and AMB exhibited acidic pH, and CHP, alkaline. NAC and AMB showed lower viable cell count than CHP. Paste AMB exhibited a higher level of antimicrobial action. AMB and NAC pastes were shown to be more cytotoxic than CHP. In contrast, in a higher dilution of CHP, a rise in cell viability was detected. Conclusion: NAC and AMB were more soluble and had acid pHs. AMB had a higher level of antimicrobial activity against E. faecalis biofilm. Cytotoxicity levels were higher for NAC and AMB pastes.
Clinical relevance: The NAC and AMB were compared with calcium hydroxide paste as intracanal medication and demonstrated promising results for clinical use. (EEJ-2021-12-209)