Cariostatic Efficacy Of Cervitec®- Und Fluor Protector® On Demineralized Fissures P. Hahn*, N. Mirnaghyan, E. Hellwig (Dental Clinic, Department Of Operative Dentistry And Periodontology, University Of Freiburg, Germany) Caries occurs mainly at retention sites for plaque, e.g. pits and fissures. It is therefore of interest to investigate the efficacy of different preventive meassures in this localization. An artificial plaque model was used to compare the cariostatic effect of Cervitec®, Fluor Protector® and Visioseal® on bacterial demineralization in artificial fissures.   88 cylindrical enamel/dentin discs (ø 5mm) were prepared out of bovine teeth. The specimens were randomly distributed among 4 groups, and embedded in acrylate resin. In each specimen, two grooves, about 200µm wide and 1500µm deep, were sawn to mimic fissures. The bottom of the fissures was placed in dentin. Then specimens were sterilized, and suspended in a tube containing a culture medium inoculated with S. mutans for 48 h. 22 specimens were taken for the initial determination of demineralization of the fissures. In the remaining specimens one fissure was treated with different substances: group (1) Cervitec® (1% Chlorhexidin, 1% Thymol), group (2) Fluor Protector® (1000ppm fluoride), and group (3) Visioseal® (fissure sealant) as positive control. In each specimen the second fissure was left untreated serving as negative control. After 24h in a sterile medium the discs were suspendend again in the S. mutans medium for ten days. Finally demineralization was determined by polarized light microscopy of sections from the specimens.   The deepest demineralization was found at the entrance of the fissures, decreasing towards the bottom, with and without preventive treatment. Demineralization was significantly reduced by Visioseal®, Fluor Protector® and Cervitec® at the bottom of the fissure. At the dentin/enamel border and at the entrance of the fissures reduction was only significant for Visioseal® and Fluor Protector®.