In vitro evaluation of probiotics microorganisms adhesion to an artificial caries model

Abstract

Objective: This in vitro study compared the adhesion of two probiotics microorganisms (Lactobacillus casei Shirota and Lactobacillus acidophilus) to an artificial caries model. Method: In total, 30 bovine teeth were longitudinally sectioned, excluding the lingual half surface. The specimens were covered with nail varnish, except for an area of 3 by 5 mm in dentin, suspended in an artificial caries solution promoted by Streptococcus mutans, and incubated at 37°C. After 14 days, the specimens were separated equally into two groups and transferred to a brain heart infusion culture media containing L. acidophilus (group A) and L. casei Shirota (group S), at 37°C. After 48 h, the exposed area of dentin was washed with 1 ml of distilled water and the caries dentin was removed and dispersed in 1 ml of saline solution. The samples of distilled water and caries dentin were diluted and inoculated in Rogosa selective Lactobacillus agar. The results in CFU/ml were analysed by the Mann-Whitney test. Results: There was no significant difference between Groups A and S for the lactobacilli count in samples of distilled water (P=0.237). Conclusions: The amount of L. acidophilus in the artificially caries dentin was significantly superior compared to L. casei Shirota (P=0.047), suggesting an inferior adhesion potential for this microorganism. © 2005 Nature Publishing Group. All rights reserved.