[Electron microscope study of bacteria in dental plaques following the application of fluorides (author's transl)].

Gels containing fluorides can have profound effects on dental plaques. These gels contain 2% fluorides in the form of sodium monofluorophosphate and sodium fluoride and are buffered to pH 6.5 when applied to teeth they: - encourage the disappearance of certain bacteria, - inhibit the division of cells and diminish their storage of glycogen, - cause a thickening of the bacterial cell wall, - lead to modifications of the bacterial cell membrane, - precipitate the degeneration of most forms of bacteria, - cause the rapid mineralisation of many bacteria. These widespread effects, and the wholesale degeneration of microbial forms, are a reflection of a major breakdown in bacterial metabolism, and provide a partial explanation for the role of fluorides in the prevention of dental caries, and are in accord with previous biochemical and microbial observations.