In Vitro Antimicrobial Activity of Various Medication Preparations on E. faecalis in Root Canal Dentin

Abstract

The purpose of this study was to evaluate the antimicrobial activity of several medication preparations in root canal dentin infected with Enterococcus faecalis. Roots of extracted bovine incisors were prepared to standardized cylindrical test specimens, 5 mm in height. The smear layer was removed and the samples were autoclaved and then incubated at 37 degrees C/5% CO2 for 24 h in brain-heart infusion (BHI) broth containing 7.0 x 10(4) colony forming units per ml of E. faecalis. The samples were washed in phosphate buffered saline and mounted to individual culture wells with sticky wax. Test medications were applied to fill the canal lumina; medication groups were: (a) sterile H2O (positive control); (b) a 10% mixture of 1.0 g Ca(OH)2 USP in 10 ml sterile H2O; (c) 10% Ca(OH)2 in 0.12% chlorhexidine gluconate (Peridex); (d) Peridex; and (e) uninoculated BHI (negative control). The samples were incubated at 37 degrees C/5% CO2 for 24 h. Dentin samples for quantitative microbiology were then obtained with consecutive sterile burs (ISO 029, 035, 042). All three experimental groups demonstrated significantly greater antimicrobial activity than the positive control (p < 0.001). Group 2 demonstrated significantly greater antimicrobial activity than Group 3 or Group 4 at all dentin depths (p < 0.05). These results suggest that 10% Ca(OH)2 may be more effective than Peridex or 10% Ca(OH)2 in Peridex for the elimination of E. faecalis from dentin tubules.

Antibacterial effect of triantibiotic mixture versus calcium hydroxide in combination with active agents against Enterococcus faecalis biofilm

“…This is in accordance with the findings of other reports 29,30,[35][36][37] . These results can be due to the similar pH values of CH solutions when combined with other irrigants or medications (Table 2).…”

“…CH is widely used as intracanal medication due to its organic tissue dissolution potential 26) , antibacterial activity 27) , and antiinflammatory capacity 28) . Since CH is ineffective in elimination of some microorganisms such as E. faecalis, to improve its antibacterial activity, it has been combined with other materials [29][30][31][32][33][34][35][36][37][38] . In the present study, to evaluate the combination potential of CH, it was combined with two established endodontic irrigants (CHX, NaOCl) and COL a medication with possible antibacterial potentials.…”

“…This model provides reconstruction of the microanatomy of dentin, simulates the chemical environment of the root canal system, and allows biofilm development 40) . Numerous studies have evaluated the antibacterial effect of CH alone or in combination with different materials using the dentin block model [30][31][32][33][34][35][36][37][38] . However, there is still controversy on whether combination of CH with other active agents enhances its antibacterial potential.…”

“…This strain easily penetrates into dentinal tubules 41) . Since this bacterium is highly resistant against different antibacterial agents, it has been used to evaluate the antibacterial effectiveness of different intracanal medications in various studies 20,[30][31][32][34][35][36][37]43) . Accordingly, this strain was selected as a measure for antibacterial property of selected medications in the present investigation.…”

In vitro effectiveness of different endodontic irrigants on the reduction of Enterococcus faecalis in root canals

“…Our findings are in corroboration with other studies thus reemphasizing that antimicrobial action of NaOCl is proportional to its concentration (3). A significant reduction in colony forming units with 0.2% CHX found in this study corroborates with the findings of other studies (13,14) which may be suggestive * Chi-square test with continuity correction was used to calculate the P-value. # Fisher's Exact Test (2-tailed) was used to identify the significant groups at 5% level.…”