Objective: To investigate the effect of a fluoride-oligomer incorporated coating material (FO) on biofilm detachment. Methods: The experimental coating material containing Bis-GMA, MMA, ethanol and photo-initiator was incorporated with fluoride-oligomer (FO). A coating material having the same chemical composition without fluoride-oligomer (Non-FO) was used as a control. Resin composite slabs (4x4x1.5 mm3) were prepared using an indirect composite (Estenia C&B, Kuraray Medical) and ground with #800-grit SiC paper. The surfaces were coated with one of two the experimental coating materials: FO and Non-FO. Non-coated #800SiC ground surface of indirect composite slabs were also used as negative control (#800SiC). Artificial biofilms were grown on three differently conditioned slabs inside an artificial mouth culture system (AMS) using freshly cultured Streptococcus mutans MT8148 suspended in phosphate buffered saline (PBS) at an OD500=2 (approximately 2x107CFU/ml), heart infusion (HI) broth with sucrose (1% final concentrations) and PBS for 20 hrs at 37°C. After 20 hours each slab with artificial biofilm was subjected to vortex (Vortex-2 Genie, Scientific Industries Inc) for 15 seconds in cool PBS. Turbidity and glucan of the retained and detached biofilms were measured using a Plate reader. In addition, surface morphology of the retained biofilm on the slabs from each group was investigated by SEM. Result: One-way ANOVA and LSD indicated that amount of retained bacteria was significantly less on FO (0.08+/-0.03) surface (p<0.05) compared to Non-FO (0.12+/-0.03) and #800SiC (0.12+/-0.01). SEM images showed that the FO had apparently thinner glucan layer surrounding the bacterial cells. While, Non-FO and #800SiC had densely cemented glucan around bacterial cells. Mushroom-like biofilm structure was prominent on the top most surface of both Non-FO and #800SiC slabs, which was not visible on FO slabs. Conclusion: Fluoride-oligomer incorporated coating material has shown the potentiality of increased biofilm detachment. This study was supported by COE Program at TMDU.