ANTIBACTERIAL EFFECTS OF SOME ROOT END FILLING MATERIALS

In addition to having good sealing ability, root end filling materials should ''ideally'' have some antibacterial activity to prevent bacter ial growth. This investigation compared the antibacterial effects of a malgam, zinc oxide-eugenol, Super EBA and a mineral trioxide aggregate on nine facultative bacteria Streptococcus fecalis, Streptococcus mit is, Streptococcus mutans, Streptococcus salivarius, Lactobacillus spec ies, Staphylococcus aureus, Staphylococcus epidermidis, Bacillus subti lis, and Escherichia coil B and seven strict anaerobic bacteria, Prevo tella (Bacteroides) buccae, Bacteroides fragilis, Prevotella (Bacteroi des) intermedia, Prevotella (Bacteroides) melaninogenica, Fusobacteriu m necrophorum, Fusobacterium nucleatum, and Peptostreptococcus anaerob ius. After growing these bacteria on solid media, freshly mixed and 24 -h set test materials were placed on the surface of these inoculated m edia and incubated in the appropriate atmosphere for 24 to 48 h at 37 degrees C. Impregnated discs with the Super EBA liquid were used as po sitive controls. The antibacterial effects of each material were measu red in millimeters and the data were analyzed using one-way and two-wa y analysis of variance and Scheffe tests to determine the statistical differences between the antibacterial effects of the test materials. I mpregnated discs with Super EBA liquid caused varying degrees of growt h inhibition for both facultative and strict anaerobic bacteria. Both types of amalgam had no antibacterial effect against any of the bacter ia tested in this study. Mineral trioxide aggregate had an antibacteri al effect on some of the facultative bacteria and no effect on any of the strict anaerobic bacteria. Zinc oxide-eugenol and Super EBA pastes had some antibacterial effects on both types of bacteria tested. Base d on the results of this study, it appears that none of the test mater ials had the complete antibacterial effects desired for root end filli ng materials.