Australasian Dentist Magazine March April 2021

Category 46 Australasian Dentist within a matrix of extracellular material that has been produced by the biofilm cells. 36 Bacterial dental plaque is perhaps the most widely studied biofilm due to its association with caries and periodontal disease and there is increasing interest in the nature of biofilms formed by Candida spp. 37 It is widely recognised that both the biofilm structure and the phenotype of cells within a biofilm can afford protection against both host defence processes and administered antimicrobial agents. 36,38 Enhanced resistance of a biofilm to an antimicrobial has been related to failure of the agent to diffuse the biofilm, sequestering of the agent within the biofilm matrix, and the presence of persister cells within the biofilm that have a low activity status that promotes their survival in the presence of an antimicrobial. Studies have shown that antimicrobial activity is elevated up to 500-fold in biofilms when compared with equivalent planktonic studies. 39 Potentially useful antimicrobial agents must therefore demonstrate activity against bacteria in both planktonic and biofilm states. 35 In this context, it is of interest that chlorhexidine at its working concentration of 0.2% does not appear to effect a total kill in a biofilm and that the essential oil-containing preparations would appear to have greater activity against microorganisms in biofilm state than planktonic phase. 35,40 Bacterial biofilm susceptibility to Citrox BC30 was exhibited at concen­ trations below 1%. However, elevated MICs were recorded against biofilms generated by the two closely related yeast species of C. albicans and C. dubliniensis . As in the planktonic assay, the MICs of the MDC30 preparations were correspondingly low for these species. Further investigation is required to explain the mechanisms behind this phenomenon. In summary, the present study has demonstrated thatworking concentrations (1‑2% v/v) of Citrox ® BC30 are effective at inhibiting the growth of a range of bacteria and Candida when cultured in either broth suspension or as a biofilm. In addition, CitroxTM MDC demonstrated activity against microorganisms exhibiting high MICs with BC30. The findings support the further investigation of both formulations of Citrox ® as potentially significant antimicrobial agents in future mouthwash preparations and other oral care products. u For a full list of references contact gapmagazines@optusnet.com.au clinical Register now for ADX Melbourne Registrations are now open for the inaugural ADX Melbourne, which will be held between Thursday, 6 – Saturday, 8 March 2021. ADX Melbourne is a place where the nation’s dental community can come together to see more, buy more, and learn more. You can experience the latest innovations, technologies and techniques as well as network with professionals from across the industry. Highlights include: u Business growth education sessions in learning labs u Clinical CPD curated by ADA NSW Centre for Professional Development u Free creche for children up to 12 years of age u Extended opening hours This free event will be held at the Melbourne Convention Exhibition Centre. Register your attendance today at: https://www.adx . melbourne/registration.html