Artificial caries produced by different oral bacterial cultures incubated with bovine dental enamel

Early caries-like lesions were formed in enamel incubated in glucose broths inoculated with different cultures of oral bacteria. Analysis of the broths by gas chromatography revealed, after appropriate incubation, the presence of lactic, succinic, formic, acetic, propionic, isobutyric, n-butyric, isovaleric or n-caproic or mixtures of these acid catabolites. Subsurface lesions formed with all acids and mixtures providing that the terminal pH dropped less than or equal to 5.6. However, the processes conformed in part only with the idealized simple diffusion phenomenon for caries formation, indicating the presence of other factors which could affect the production of lesions in biological systems.