RESUMO
PURPOSE: To evaluate the effects of porcine mucin- and carboxymethylcellulose-based (CMC) solutions on the inhibition of demineralization of pre-demineralized bovine enamel and dentin in vitro. Additionally the sugar substitutes sorbit or xylit were added to the various solutions. METHODS: 54 enamel and dentin samples were prepared from 14 freshly extracted permanent bovine central incisors. The samples were demineralized (pH 5.0 for enamel and pH 5.5 for dentin; 14 days) and subsequently exposed to either mucin- or CMC-based solutions combined with xylit and sorbit at pH 5.5. After in vitro exposure, the specimens were cut perpendicular to the enamel/dentin surface and the sections were ground (4000 grit) to a uniform thickness (100 microm). Mineral loss and lesion depths were evaluated from microradiographs with a dedicated software package (TMR 2.0.27.2). RESULTS: For both dental hard tissues, storage in the mucin-containing solutions resulted in significantly higher lesion depths (deltaLD), but lower mineral loss values (deltadeltaZ) compared to the CMC-containing solutions (P< 0.05; 2-way ANOVA). For the dentin specimens, significant differences in deltadeltaZ were observed between sorbit and xylit (P< 0.05; 2-way ANOVA). The mineral loss and lesion depths of the enamel specimens did not differ significantly after storage in the various solutions (P> 0.05; Bonferroni post hoc test). For the dentin specimens stored in the solution containing mucin/xylit the mineral loss was significantly decreased compared to the other mucin groups as well as to the CMC/xylit solution (P< 0.05; Bonferroni post hoc test).