ABSTRACT
Objectives: This is an in vitro study to develop a formulation of a hypochlorite solution for root canal irrigation
that lacks a chlorinated odor. The antibacterial effect, tissue dissolution efficacy,
and the cytotoxicity of the solution were assessed in cell culture and were compared
with those of commercial sodium hypochlorite (NaOCl) solutions. Materials and Methods: Trichloroisocyanuric acid (TCA) was used as the source of hypochlorite ions in solution.
All required properties of the NaOCl irrigant were evaluated and compared with those
of original 2.5% NaOCl solutions currently in use. Results: Our results revealed that a TCA 3.5% + 1/6 Buffer-1 solution passed the short-term
stability test. Moreover, no odor of chlorine gas was detected by three independent
observers. The hypochlorite ion content and pH were stable over an incubation period
of 4 weeks. The new solution did not differ from commercial products in terms of the
dissolution property on bovine pulpal tissue (P > 0.05). Moreover, the antibacterial effect of this solution on Enterococcus faecalis
did not differ from that of the commercial products (P > 0.05). In addition, our biocompatibility analysis demonstrated no difference among
the tested solutions (P > 0.05). Conclusions: According to the results of all properties tested, TCA 3.5% + 1/6 Buffer-1 could
be considered an option for NaOCl irrigation with the benefit of no detectable chlorine
odor.
Key words:
Hypochlorite solution - lacks a chlorinated odor - root canal irrigant
