The anticaries effect of a food extract (Shiitake) ina short-term clinical study

The main objective was to investigate whether low-molecular-weight fraction of edible mushroom shiitake extract (Lentinusedodes) possesses caries-preventive properties. The study was designed as a double-blind, three-leg, cross-over, randomized,controlled clinical trial carried out on two series of volunteers at the University of Gothenburg, and the Academic Centrefor Dentistry Amsterdam. Volunteers rinsed twice daily with a solution containing low-molecular-weight fraction of ediblemushroom, placebo (negative control without active ingredients), or Meridol (positive control, AmF-SnF2) for two weeks, with atwo-week washout period between each rinsing period. Changes in the acidogenicity of dental plaque before and after a sucrosechallenge, shifts in microbial composition, and plaque scores were determined. Frequent rinses with shiitake reduced themetabolicactivity of dental plaque. No reduction of plaque scores and no inhibition of the production of organic acids in plaque was found.Minor differences inmicrobial composition between test sessions were found. To conclude, the results indicate that shiitake extracthas anticariogenic potential, but not to the same extent as the positive control.