ABSTRACT
This chapter describes films that form on dental tissues since early in the history of science. Film fermenters have been used to examine the effects of bacterial antagonism, or of commensal dependence, on the success of mixed species in establishing growing films on surfaces of teeth. The factors affecting growth, substantivity, and the effect of diffusion on the chemical profile of the film have been discussed for microbial fermenters in stirred conditions. The complexity of the oral environment and ethical problems associated with the study of disease processes in human subjects inevitably directed attention to the development of laboratory models. The salivary systems differ significantly from dental plaque in the spatial distributon of the bacteria, in inoculum density, and in the chemical composition of the aqueous environment of the bacteria. Most of the bacterial metabolic activity is associated with shed epithelial cells and these cells can be seen under a microscope to harbor dense clumps of bacteria.
