A study has been made to determine the inhibitory action upon the progress of dental caries of two trace elements (fluorine and molybdenum) combined with chlorohexidine with the goal of increasing the efficiency of fluoride treatment. However, the results obtained show that the chosen combination of trace elements did not lead to a substantial increase in cariostatic action. Combined use of fluorides and chlorohexidine was seen to exert an inhibitory action on the progress of dental caries.