European Journal of Dentistry

Objective: The aim of this study was to evaluate the antibacterial property of glass-ionomer ce-ment (GIC) containing propolis against Streptococcus mutans and its effect on the in vitro S. mutans biofilm formation. Methods: Ethanolic extract of propolis (EEP) was prepared at two concentrations as 25 and 50%. Three different experimental GIC disks were prepared using pure liquid and liquid solutions diluted with 25 and 50 percent of EEP concentrations. Minimum inhibitory concentration (MIC) of EEP on the growth of S. mutans ATCC 25175 was determined by using agar dilution method. Agar diffusion test and an in vitro S. mutans biofilm assay for GIC disks with and without EEP were performed. Results: MIC values of Turkish propolis for S. mutans ATCC 25175 was found as 25 µg/mL. Experi-mental GICs containing propolis exhibited inhibition zones and their dry biofilm weights were less than the pure GIC. The bacterial density was lower in the GIC containing 50 % EEP. Conclusions: A distinct antibacterial and antibiofilm efficacy of propolis containing GIC on S. mu-tans has been observed. Although further research is needed to show clinical results, antibacterial GIC containing propolis would be a promising material for restoration. (Eur J Dent 2012;6:428-433) Key words: Propolis; Streptococcus mutans; glass-ionomer cement; biofilm formation; antibacte-rial effec