Evaluation of the antibacterial substantivity of several intra-canal agents (original) (raw)
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Antimicrobial Substantivity of Chlorhexidine-Treated Bovine Root Dentin
Journal of Endodontics, 2000
Previous studies have demonstrated antimicrobial substantivity in root canal dentin up to 7 days after treatment with chlorhexidine. This in vitro study assessed the antimicrobial substantivity of chlorhexidine-treated bovine root dentin over a period of 21 days. Sixty standardized bovine root sections were randomly divided into three equal groups, and their canals immersed in one of the following solutions: (i) sterile saline; (ii) 2.5% NaOCI; or (iii) 0.2% chlorhexidine (CHX). Half the specimens in each group were treated with the solution for 5 min and the other half for 7 days. After solutions were removed, the specimens were incubated at 37°C in Brain Heart Infusion broth containing Enferococcus faecalis (ATCC 29212). A fresh inoculum was added to the broth every other day over a 21-day period. The canals were then enlarged with sterile burs, and the dentin shavings collected and cultured for the presence of cultivable bacteria in the dentinal tubules. Specimens treated with CHX for 7 days demonstrated significantly less dentin colonization by E. faecalis than the other specimens. CHX has potential as an intracanal medicament, if it can be applied for a period of at least 7 days.
Antibacterial substantivity of a new antibiotic-based endodontic irrigation solution
Australian Endodontic Journal, 2012
The aim of this study was to evaluate the residual antibacterial activity of Tetraclean, MTAD and 5.25% sodium hypochlorite (NaOCl) in bovine root dentin in vitro. One hundred and ten dentin tubes prepared from bovine incisor teeth were infected in vitro for 14 days with Enterococcus faecalis. Thereafter, the specimens were divided into five groups as follows: Tetraclean; MTAD; 5.25% NaOCl; infected dentin tubes (positive control); and sterile dentin tubes (negative control). Dentin chips were collected using round burs into tryptic soy broth and after culturing, the number of colony-forming units (CFU) was counted. The number of CFU in all experimental groups was minimum after treatment, and the results obtained were significantly different from each other at any time period (P < 0.05). The Tetraclean group showed the most effective antibacterial action at all five experimental periods (P < 0.05). MTAD group showed the least antibacterial activity after treatment. However, at days 7, 14, 21 and 28 MTAD showed more effective antibacterial action than NaOCl. In each group, the number of CFU increased significantly by time-lapse (P < 0.05). In conclusion, the residual antibacterial activity of Tetraclean was significantly greater than MTAD and 5.25% NaOCl.
Substantive antimicrobial activity in chlorhexidine-treated human root dentin
2002
The aim of this in vitro study was to assess the substantive antimicrobial activity of different medicaments in human root dentin. Study design. Canals of 98 roots were enlarged to standard size and medicated for 7 days with the following: (1) 2% chlorhexidine (CHX) gel, (2) 0.2% CHX gel, (3) 2% CHX solution, (4) Ca(OH) 2 , (5) Ca(OH) 2 ϩ 0.2% CHX gel, (6) 2% CHX solution ϩ a 25% CHX-containing controlled-release device, (7) saline, and (8) gel vehicle. After medication, canals were inoculated with Enterococcus faecalis for 21 days. Dentin samples were collected with Gates-Glidden burs into brain heart infusion broth, and bacterial growth was assessed with spectrophotometric analysis of optical density after 72 hours of incubation. Results. Mean optical densities were significantly lower for groups with 2% CHX (1, 3, and 6) when compared with those of the controls (P Ͻ .05, analysis of variance with the Tukey test). Other groups did not differ significantly from the controls. Conclusions. Canal dressing for 1 week with 2% CHX may provide residual antimicrobial activity against E faecalis.
New intracanal formulations containing doxycycline or chlorhexidine against Enterococcus faecalis
The journal of contemporary dental practice, 2014
The present study aims to evaluate the antimicrobial effect of two new intracanal preparations against E. faecalis. Thirty single-rooted human canine teeth were used. The crowns were removed and the roots were instrumented using a conventional technique. Three groups of ten teeth each were infected with 108 CFU/ ml of E. faecalis for 21 days. The root canals were flled with new intracanal medications containing 3% doxycycline hydrochloride (DX) or 2% chlorhexidine digluconate (CHX). Ten teeth received no medication (NM)-negative control. Microbial samples were obtained 21 days after contamination: 14 days under the effect of the intracanal medications and 7 days after replacing the medications by BHI broth. The samples were homogenized, diluted, seeded on BHI agar and incubated for 48h/36°C. The number of colony forming units (CFU/ml) was obtained and analyzed statistically. All intracanal dressings significantly reduced the number of bacterial cells in the root canal after 14 days ...
Journal of Endodontics, 2000
Root canal dentin acquires antimicrobial substantivity after exposure to chlorhexidine gluconate (CHX) for 1 wk. Therefore development of a vehicle for delivery of CHX as an intracanal medication is desirable. This in vitro study assessed the efficacy of two CHX delivery vehicles, a controlled-release device and a gel, to affect antimicrobial substantivity of bovine root dentin. Sixty bovine incisor root specimens were prepared with standardized length (10 mm) and canal diameter (3.3 mm), and coated externally with nail polish. Specimens were divided into four equal groups and their canals medicated for 7 days with either: (i) an experimental controlled-release device containing 25% CHX that was immersed in sterile saline; (ii) 2% CHX gel; or (iii) Ca(OH) 2 paste. Sterile saline was used as the positive control. After medication, the canals of the specimens were inoculated with Enterococcus faecalis for 21 days. Root canal dentin samples ranging in depth from 0.1 to 0.45 mm were then obtained using sterile round burs of ascending diameter. Each dentin sample was placed in a separate test tube containing Brain Heart Infusion broth and incubated for 24 h. The optical density (OD) of the broth was then measured spectrophotometrically at 540 nm. The positive control showed significantly higher mean OD values (oneway ANOVA and Tukey's Studentized Range Test; p < 0.001) than the three test groups. The CHX controlled-release device group showed significantly lower OD values than the Ca(OH) 2 group; however only at dentin depths up to 0.2 mm. In contrast, the CHX gel group consistently showed significantly lower OD values than both the CHX controlled-release device and Ca(OH) 2 groups. These results suggest that bovine root canals medicated with 2% CHX gel for 7 days acquire antimicrobial properties for at least 21 days.
Antibacterial efficacy of several intracanal medicaments for endodontic therapy
Dental Materials Journal, 2017
The antibacterial efficacy of intracanal medicaments for 2 and 7 days, in open apex root canals contaminated with Enterococcus faecalis biofilms was compared. One hundred and thirty-eight standardized uniradicular human roots were inoculated with E. faecalis. Colony forming units (CFU) were recorded before and after medication. Samples were divided in two (2/7 days), and subdivided (n=8/group): triple antibiotic paste (TAP); double antibiotic paste (DAP); dental base paste (DBP), consisting of calcium hydroxide, propylene glycol and calcium carbonate; DBP+0.2% chlorhexidine (CHX); DBP+0.2% cetrimide (CTR); DBP+0.2% CHX+0.2% CTR; 2.5% sodium hypochlorite (NaOCl); and distilled water. At both periods TAP, DAP, DBP+0.2% CHX, DBP+0.2% CTR and DBP+0.2% CHX+0.2% CTR exhibited no growth (NG) of E. faecalis. Distilled water and 2.5% NaOCl obtained the lowest CFU reduction. No growth with DBP was reached only at 7 days. CHX and/or CTR pastes were as effective as DAP and TAP. A 2-day period provided an effective disinfection.
Introduction: Enterococcus faecalis (E. faecalis) is a microorganism commonly detected in persistent endodontic infections. Eradication of this organism from an infected root canal remains a significant clinical challenge for modern endodontic treatment. So, this in vitro study was conducted to compare antimicrobial effect of some root canal medicaments on E. faecalis. Materials/Methods: A total of 50 E. faecalis strains (49 strains were selected randomly from positive cultures together with a standard E. faecalis strain ATCC 29212) were used in the study. Inoculum for each bacterial strain was prepared in a turbidity of 0.5 on McFarland scale. The prepared discs of the three intracanal medicaments; chlorhexidine, diapex and diclofenac; together with readymade discs of amoxicillin and doxycycline were distributed on blood agar and Mueller-Hinton agar plates inoculated with an E. faecalis suspension previously prepared. Antimicrobial activity was assessed by measuring the diameters of the zones of growth inhibition surround the discs after incubation at 37°C for 24 hours and then after 48 hours. Results: All strains (100%) were sensitive to chlorhexidine even though strains that showed resistance to one or both of antibiotic used (amoxicillin, doxycycline). On the other hand, all strains (100%) were resistant to diapex and diclofenac even standard strain. Sixty eight percent of the tested strains were sensitive to doxycyline and 44% of them were sensitive to amoxicillin. Conclusion: Under the conditions of this study, chlorhexidine is very effective against E. faecalis and can be considered as the most powerful root canal medicament compared to other intracanal medicaments tested. Controversially, no zones of inhibition were detected around diapex and diclofenac. Keywords: Enterococcus Faecalis; Root Canal Medicaments; Antibacterial Effect; Chlorhexidine; Diapex; Diclofenac; Amoxicillin; Doxycycline.
Antimicrobial activity of common endodontic materials on Enterococcus faecalis NEWP 0012
The elimination of the microorganisms in its totality, during the endodontic therapy, although desired, is hard to be achieved. Even after the canal filling, the microorganisms are able to be into the dentinal mass and into the periapical region. This essay aims to evaluate the antimicrobial activity of endodontic materials against to the Enterecoccus faecalis NEWP 0012. The inoculation of this microorganism in the glass plates was done using swabs pressing the cotton against the wall of the pipe. The bacterial suspension was sowed evenly on the sterile surface of the Ágar MH. The plates were incubated by aerobic conditions, in a constant temperature in the range of 35º a 37°c, for 24 hours. The endodontic materials tested were: Sealer 26, Endofill, AH plus, MTA Filapex, calcium hydroxide paste associated to the chlorhexidine, Maxxion R glass ionomer, MTA and MTA HP. After material manipulation, they were impregnated into absorbent paper discs of 5mm of diameter and distributed sporadically on the plates that contained the microorganism. The experimental data were obtained by the measurement of the inhibition halo in the period of 24h, 72h, 7, 15 and 21 days; thus, the microorganism was classified as resistant or sensible to the different products. From the results, it was possible to verify that the calcium hydroxide paste associated to the chlorhexidine presented superior antimicrobial activity on Enterecoccus faecalis NEWP 0012. It was concluded that the calcium hydroxide paste associated to the chlorhexidine has satisfactory antimicrobial activity against the Enterecoccus faecalis NEWP 0012 in the period between 24h to 21 days.
Revista Odonto Ciência, 2011
Purpose: The aim of this study was to verify the antimicrobial effect of calcium hydroxide and iodoform on Enterococcus faecalis with different exposure times evaluating the bacterial morphologic alterations. Methods: The antibacterial action was investigated in culture broth after zero, seven, fourteen and twenty-one days. Five mL samples were analyzed morphologically on the seventh day by transmission electron microscopy. The data of the antibacterial test were analyzed by Fisher's exact test. Results: The results revealed that between the seventh and fourteenth day, there was a decrease in bacterial growth with both medicaments (P=0.098), where they were eliminated between the fourteenth and twenty-first day. Transmission electronic microscopy showed alterations in the morphologic structures. Conclusion: It concluded that both medicaments kill Enterococcus faecalis, with an exposure time of 7 to 14 days, where no cell viability is seen after this period due to irreversible alterations in bacterial cell morphology.