Photocatalytic TiO2 particles confer superior antibacterial effects in a nutrition-rich environment: an in vitro study

BACKGROUND Given that periapical bacterial infections are considered as one of the causes of endodontic treatment failure, and biomechanical methods may not be able to eliminate bacteria resistant to endodontic treatment, including Enterococcus faecalis; therefore, this study was conducted to compare the antibacterial effects of Golpar and Kakoti extracts with calcium hydroxide and chlorhexidine against E. faecalis. METHODS At first, Heracleum persicum (Golpar) and Ziziphora tenuior L. (Kakoti) plants were extracted by ethanol solvent using the cold maceration method and a vacuum distillation apparatus. E. faecalis ATCC 29212 was used as the standard strain in all stages of the experiment. Antibiogram, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) tests were performed to evaluate the antibacterial activity of the prepared extracts. The anti-biofilm activity of the extracts was evaluated similar to MIC evaluation but with a longer incubation time and analyzed by ELISA at a wavelength of 492 nm. RESULTS The antibiogram test showed a growth inhibition zone diameter of 4 mm only for chlorhexidine. In addition, chlorhexidine exhibited the highest inhibitory and bactericidal activities in the MIC and MBC tests, respectively (MIC / MBC < 1.562 mg / mL). The MIC of Golpar, Kakoti, and Golpar + Kakoti extracts was determined to be 50 mg / mL. No significant inhibitory activity was observed for calcium hydroxide either alone or in combination with the plants' extracts. The MBC of Kakoti extract was 50 mg / mL, and the other compounds had an MBC greater than 100 mg / mL. CONCLUSIONS The present in vitro study showed that the highest inhibitory activity against E. faecalis was related to chlorhexidine; however, Golpar and Kakoti extracts at a concentration of 50 mg / mL exhibited a proper inhibitory activity compared to calcium hydroxide. Therefore, further studies are recommended to be conducted in the future. KEYWORDS Enterococcus faecalis, Ziziphora tenuior L., Heracleum persicum, Chlorhexidine, Calcium Hydroxide, Antibacterial effects.

Download Full-text

Comparison of Antimicrobial Activity of Fluoride Varnishes Against Streptococcusmutans and Lactobacillus acidophilus: An In Vitro Study

Iranian Journal of Pediatrics ◽

10.5812/ijp.111422 ◽

2021 ◽

Vol In Press (In Press) ◽

Author(s):

Banafsheh Soleimani ◽

Hamidreza Goli ◽

Mahsa Naranjian ◽

Seyed Jaber Mousavi ◽

Azam Nahvi

Keyword(s):

Lactobacillus Acidophilus ◽

Antibacterial Properties ◽

In Vitro Study ◽

Inhibition Zone ◽

Vitro Study ◽

Diffusion Method ◽

P Value ◽

Antibacterial Effects ◽

The Mean

Background: Topical fluoride products such as varnishes prevent dental caries by limiting demineralization and antibacterial properties. The structural and metabolic characteristics of cariogenic microorganisms are different from each other. Also, the formulation properties, concentration, and release behavior of fluoride vary in different varnishes. Objectives: In this study, we investigated the antibacterial effects of three types of common fluoride varnishes against two cariogenic bacteria of Streptococcus mutans (S.M.) and Lactobacillus acidophilus (L.A.). Methods: In this in vitro study, antibacterial effects of MI varnish [containing calcium phosphopeptide-amorphous calcium phosphate (CPP-ACP)], Polimo (containing xylitol), and FluoroDose varnishes were evaluated using disc diffusion method via measuring the diameter of the inhibition zone. The antibiotics of erythromycin and ampicillin were used as the positive control of the test. Analysis of variance (ANOVA) and post hoc tests were applied to compare the mean of non-growth zone diameter in the studied groups. Data were analyzed by SPSS 16. The statistical significance level was determined as P-value < 0.05. Results: The antibacterial effect of each varnish was optimal against both bacteria. In comparison, the mean diameter of the inhibition zone in MI varnish was significantly (P-value=0.019) higher than Polimo and FluoroDose brands on S.M.; however, this difference was not statistically significant for L.A. Furthermore, Polimo and FluoroDose varnishes showed similar antimicrobial effects against these bacteria. Conclusions: The use of these varnishes seems to be suitable for preventing tooth decay. MI varnish is preferable because of its higher antibacterial properties.

Download Full-text