RESUMO
PURPOSE: To evaluate five different mouthrinses with respect to fluoride uptake by sound and demineralized dentin. METHODS: The pharmacy-made mouthrinses contained either (1) 0.06% chlorhexidine, (2) 0.025% sodium fluoride, (3) 0.06% chlorhexidine and 0.025% fluoride (NaF) or (4) water (control). Additionally, the commercially available solution (5) Chlorhexamed Lösung 0.06% + F (GlaxoSmithKline) was used. 240 cylindrical dentin blocks were obtained from 120 bovine incisors. Half of the specimens were divided into five groups of 24 samples each and immersed in one of the mouthrinses (2.5 ml/specimen, 30 seconds). Accordingly, the remaining specimens were again divided into five groups of 24 specimens each; prior to treatment with one of the mouthrinses, these specimens were subjected to a demineralization procedure (lesion depth: 90-100 microm) using Buskes' solution for 6 days. All specimens were assessed for KOH-soluble fluoride and structurally bound fluoride immediately after treatment. Structurally bound fluoride was determined in three successive layers of 30 microm each. RESULTS: Compared with all other mouthrinses, only the application of NaF resulted in higher amounts of KOH-soluble fluoride, and, in the outer layer, of structurally bound fluoride in both sound and demineralized dentin. Similarly, in the deeper layers, only the NaF groups showed elevated fluoride levels.