Effect of Three different fluoride Varnishes on Streptococcus Mutans and Lactobacillus Biofilm: An Vitro Study

Abstract

Introduction: Fluoride varnish is quickly and easily applied without the need for bulky mouth trays or suctioning of saliva. This is especially helpful for infants and toddlers. Aim: The aim of this study was to evaluate and compare the effect of three different fluoride varnishes (Durashield, Flour Protector and Bifluoride 10) on streptococcus mutans and lactobacillus count (in vitro study). Materials and methods : Total of 144 acrylic discs were divided into two main equal groups of 72 discs in each (group A: for examination of Streptococcus mutans and group B: for examination of Lactobacillus ); each group was further subdivided into four equal subgroups based on the type of varnish applied to the disc surface (A1, B1: Durashield; A2, B2: Fl protector; A3, B3: Biflouride; A4, B4: untreated discs served as control). Saliva collected from single volunteer was poured into tubes until the discs were completely immersed and incubated for 24h, 48h and 5 days. Six discs from each subgroup were taken out from tubes every time and sonicated in saline. Suspensions were been plated on selective media for Streptococcus mutans and Lactobacillus . The numbers of colony-forming units (CFU/mL) on suitably diluted plates were been determined. Results : For all tested subgroups, the lowest amount bacterial count of Streptococcus mutans and Lactobacillus was observed during the first 24 h, followed by a significant increase over the following 4 days. Biflouride subgroups had the lowest values of viable Streptocoocusmutans and Lactobacillus counts during all test periods. In comparison Durashield with Flour protector subgroup difference of viable counts of streptocoocusmutans and lactobacillus was observed but statistically non-significant. Conclusions : Biflouridevarnish exhibited the greatest antibacterial effect ( Streptococcus mutans and Lactobacillus ) compared to Durashield and flour protector. Fluor protector varnish showed the same inhibitory effect of Durashildvarnish despite Flour protector had lower fluoride concentration than Durashield.