Minimizing Concentration of Sodium Hypochlorite in Root Canal Irrigation by Combination of Ultrasonic Irrigation with Photodynamic Treatment

Abstract

Concentration of sodium hypochlorite (NaOCl) is positively correlated with its effectiveness in root canal disinfection but negatively correlated with its biocompatibility. The objective of this in vitro study was to compare the bactericidal effects among ultrasonic irrigation with different concentration of NaOCl alone or together with photodynamic treatment (PDT) against Enterococcus faecalis (E. faecalis) in infected root canals. One hundred and twenty bovine root canals contaminated with E. faecalis were randomly distributed into 12 groups treated with different disinfection methods: PDT, ultrasonic irrigation with NaOCl at different concentrations (0.5%, 1.0%, 2.0%, 2.5% and 5.25%), and ultrasonic irrigation with NaOCl at different concentrations plus PDT. Data of microorganism load were collected before and after disinfection and analyzed by one-way ANOVA and LSD tests. Significantly enhanced antibacterial effects were noticed in groups treated by PDT plus 2.0% or 2.5% NaOCl irrigation (P < 0.05). No statistical differences existed in bactericidal efficacy among groups of PDT plus ultrasonic irrigation with 2.0%, 2.5% or 5.25% NaOCl, and ultrasonic irrigation with 5.25% NaOCl alone (P > 0.05). Our study confirmed the feasibility to reduce the concentration of NaOCl to a safer level while maintaining its antibacterial efficiency through synergistic effect of PDT with NaOCl ultrasonic irrigation.

Antimicrobial Photodynamic Therapy against Endodontic Enterococcus faecalis and Candida albicans Mono and Mixed Biofilms in the Presence of Photosensitizers: A Comparative Study with Classical Endodontic Irrigants

“…As expected, 3% NaOCl had the best final outcomes. In fact, NaOCl at different concentrations, is considered an excellent irrigant solution in endodontics (Jeansonne and White, 1994; Siqueira et al, 2007; Mohammadi, 2008), nevertheless it also displays high toxicity levels toward the host tissues (Estrela et al, 2002; Önçaǧ et al, 2003; Trevino et al, 2011; Wang et al, 2015). …”

“…In the endodontic field, aPDT has emerged as an optional extra to classical irrigation solutions in root canal asepsis (Bonsor et al, 2006a,b) such as sodium hypochlorite (NaOCl), chlorhexidine gluconate (CHX) and ethylenediamine tetraacetic acid (EDTA). The NaOCl solution is the most widely used in endodontic treatment (Siqueira et al, 2007; Mohammadi, 2008; Vaziri et al, 2012; Wang et al, 2015) albeit with some degree of toxicity. To avoid this toxicity, other root canal asepsis approaches with lower or insignificant toxicity should be implemented.…”

Role of extracellular DNA in Enterococcus faecalis biofilm formation and its susceptibility to sodium hypochlorite

“…14 Therefore, there have been several alternative approaches proposed to improve the effectiveness of lower-concentration NaOCl solutions to avoid extensive tissue damage; however, these options have many limitations, including the requirement of inconvenient equipment. [15][16][17][18][19] Since eDNA is an essential component of E. faecalis biofilm, it can be speculated that its inhibition using a simple agent can be another strategy for effective biofilm removal. However, to our knowledge, there has been little information regarding the effect of eDNA on E. faecalis biofilm in endodontic study models.…”

Photodynamic Antimicrobial Chemotherapy for Root Canal System Asepsis: A Narrative Literature Review

“…In category I, 16 in vitro studies, only 5 (31%) [ 57 – 61 ] reveal best antimicrobial PDT outcomes when compared with sodium hypochlorite (NaOCl) in range of 0.5 to 6%. Only one study performed by Nagayoshi et al [ 62 ] reveals equal results between PDT and NaOCl; the remaining 10 (62.5%) studies [ 63 – 72 ] showed PDT outcomes unhelpful when compared with NaOCl as a classical irrigant solution, in concentration range of 0.5 to 6%. In category II, 6 (21%) papers [ 35 , 58 , 73 – 76 ] were analysed ( Table 2 ).…”