Abstract
ObjectivesThe aims of this study were to (1) investigate the relative time-dependent disruption and bactericidal effects of detergent-type surfactants on single- or dual-species biofilms of root canal isolates and (2) to examine the utility of polygonal graphs for depiction of biofilm disruption and cell killing.Materials and methodsSingle-species biofilms of Streptococcus sanguinis, Enterococcus faecalis, Fusobacterium nucleatum and Porphyromonas gingivalis were grown on nitro-cellulose membranes for 72 h and immersed in Tween®80, cetyltrimethylammoniumbromide (CTAB), and sodium dodecyl sulphate (SDS) for 1-, 5- or 10-min (n = 3 per test). The number of viable and non-viable bacteria “disrupted” from the biofilm and those “remaining-attached” was determined using a viability stain in conjunction with fluorescence microscopy. The data were analysed using non-parametric Kruskal-Wallis test with 5% significance level.ResultsGram-negative obligate anaerobes were more susceptible to cell removal than gram-positive facultative anaerobes. The majority of cells were disrupted after 1-min of exposure; however, the extent varied according to the agent and species. CTAB and SDS were more effective than Tween 80™ at disrupting biofilms and killing cells but all agents failed to achieve 100% disruption/kill.ConclusionsBiofilm disruption and cell viability were influenced by the species, the test agent and the duration of exposure. CTAB and SDS were more effective in biofilm disruption than Tween 80™. Graphical depiction of biofilm disruption- and viability-outcomes provides an alternative means of simultaneously visualising and analysing relative efficacy in different domains.Clinical relevanceSurfactants were not as effective at biofilm disruption as NaOCl but may be added to other non-disruptive antibacterial agents to enhance this property.
Highlights
Root canal treatment (RCT) fails to predictably eradicate bacteria in the apical anatomy even after using potent antibacterial irrigants [1, 2]
The present study investigated the relative time-dependent disruption and bactericidal effects of detergent-type surfactants on single- and dual-species biofilms of root canal isolates and explored the utility of the disruption/killing index to depict the outcomes simultaneously, as previously proposed [4]
S. sanguinis and E. faecalis were incubated at 37 °C in air supplemented with 5% CO2 for 48 h, while P. gingivalis and F. nucleatum were incubated in an anaerobic cabinet (Don Whitley Scientific Ltd., Shipley, UK) at 37 °C for 72 h
Summary
Root canal treatment (RCT) fails to predictably eradicate bacteria in the apical anatomy even after using potent antibacterial irrigants [1, 2]. The encasement of bacteria within the root canal biofilm has been suggested as an explanation for this failure in therapy [3], emphasising the importance of biofilm disruption to facilitate subsequent and further anti-microbial action. Antibacterial agents’ actions on biofilms may yield diverse outcomes that include killing, either with- or without disruption, in a time-dependent and dose-dependent manner [4]. CHX and iodine were effective at bacterial killing but not disruption, whilst EDTA showed biofilm disruption activity but exhibited lesser antimicrobial potential [4]. Surfactants can act as dispersants and are classified into non-ionic, cationic and anionic. Polysorbate 80 (Tween 80TM) is a non-ionic surfactant that is added to commercially available irrigants (MTAD [3% Doxycycline, 4.25% citric acid, 0.5% Tween 80TM] [Dentsply Tulsa dental, Tulsa, OK]). The antibacterial effect of MTAD against E. faecalis biofilm was not affected by the elimination of Tween 80TM [7]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
