The effect of propolis exposure on microhardness of human enamel in vitro

Propolis is a resinous wax-like material that is used by bees as a glue-lik e matrix in their hives. The in vitro effect of propolis solutions was inve stigated on the microhardness of human dental enamel. The calcium concentra tion of the solution was 7.8 ppm, the pH values varied between 5 and 6. The fluoride concentration was negligible. The Vickers hardness number of expo sed enamel showed a steady increase with the percentage of propolis in the solution. The microhardness increase may be attributed to particular compon ents of mineralization activity in propolis.