PREVENTION OF CARIOGENIC DENTAL PLAQUE - STUDY OF THE STRUCTURES IMPLICATED IN THE STREPTOCOCCUS-MUTANS AND STREPTOCOCCUS-SOBRINUS ADHESIONAND COAGGREGATION

Cariogenic dental plaque may be assimilated to a biofilm resulting fro m the adhesion of S. mutans, then from the coaggregation of other stre ptococci, or other genus. We used a static monospecific biofilm model. Supports or bacteria were treated with inhibitors before adhesion in order to clarify the nature of adhesins responsible for the primary ad hesion of S. mutans and S. sobrinus on Tygon(R). To determine the bind ings of coaggregation, inhibitors were applied on one-day-old biofilms . Analysis of effects were performed by automatic inoculator Spiral (I nterscience) for microbiological methods, and by SEM JEOL 5400 LV for microscopic methods. In the aim of preventing adhesion: and coaggregat ion, different traps were assayed : sugars, chemical inhibitors such a s F- and EDTA salts. Of these, only the latter showed efficiency. This confirmed the role of bivalent mineral ions and electrostatic attract ion forces in the adhesion and coaggregation of streptococci.