Limitations of Mold Establishment in Oral Cavity

Abstract

A survey of the mold population on the oral mucous membranes from 165 dental students was attempted. Swabs were streaked on plates of Littman''s medium containing bacitracin and chloromycetin. Nine of the plates (5.4%) contained one to three mold colonies. Four of 40 brain heart infusion agar plates streaked with sterile swabs contained one to three similar mold colonies. Because molds fail to colonize in the oral cavity, the following study was performed. Brain heart infusion pour plates containing either whole saliva or Seitz filtered saliva were prepared. The agar surfaces were streaked with species of Aspergillus and Penicillium and incubated at 37[degree]C for 24 hours. Good growth of the mold species occurred in the presence of the filtered saliva while no growth was evident in the presence of whole saliva. An increase of 0.1% in the dextrose concentration of the brain heart infusion agar supported good growth of the mold species in the presence of whole saliva. Salivary specimens taken from 10 individuals who had rinsed with 10 ml of a 20% dextrose solution were free of sugar within 10 to 15 minutes. The rapidity with which dextrose is eliminated from the oral cavity may be a limiting factor in the establishment of molds in the mouth.