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Abstract Streptococcus mutans is the primary oral caries-forming bacteria, adept at producing “sticky” biofilms via the synthesis of insoluble extracellular polysaccharides (EPS), catalyzed by glucosyltransferases (GTFs). To circumvent the use of broad-spectrum antibiotics to combat these bacteria, this study sought to modify existing EPS-targeting small molecules with the ultimate goal of producing anti-biofilm polymer surfaces specifically targeting S. mutans. To achieve this, a known GTF inhibitor (G43) was modified with methoxy or tetraethyleneglycol substitutions in different positions (nine derivatives, tested at 50-µM) to pinpoint potential sites for future methacrylate functionalization, and then assessed against single-species S. mutans biofilms. As expected, the compounds did not diminish the bacterial viability. In general, the compounds with methoxy substitution were not effective in reducing EPS formation, whereas the tetraethyleneglycol substitution (G43-C3-TEG) led to a decrease in the concentration of insoluble EPS, although the effect is less pronounced than for the parent G43. This aligns with the reduced GTF-C activity observed at different concentrations of G43-C3-TEG, as well as the consequent decrease in EPS formation, and notable structural changes. In summary, this study determined that G43-C3-TEG is non-bactericidal and can selectively reduce the biofilm formation, by decreasing the production of EPS. This molecule will serve to functionalize surfaces of materials to be tested in future research.

OBJECTIVES: Calcium hydroxide cements have been largely used in deep cavities due to their abilities to stimulate dentin formation. However, their resistance can be relatively low and their solubility relatively high, in many instances. This study evaluated water sorption and solubility of different calcium hydroxide cements, in order to show alterations that may reduce their effectiveness. MATERIAL AND METHODS: Five discs (20 mm in diameter and 1.5 mm thick) of three different materials (Biocal®, Dycal® and Hidro C®) were prepared with the aid of a ring-shaped metallic matrix. After being stored at 37ºC for 24 h, the discs were weighed on a precision weight scale, dehydrated and weighed again. Immediately after weighing, discs were stored for a week in 50 mL of distilled water at 37ºC and, then, weighed again, dehydrated and submitted to a new weighing. The loss of soluble material and its water sorption was obtained from the difference between the initial and the final dry mass of each disc, after 1 week of immersion in water. Data were analyzed for significant differences by two-way ANOVA and Tukey's test (p

Glass ionomer based materials are clinically popular in several areas of restorative dentistry, but restoration of cervical lesions has proven particularly successful. Various etiologies, conformations, locations and structural characteristics make non-carious cervical lesions more challenging to adhesive restorative procedures and marginal seal in the long run. Due to their characteristics, glass ionomer cements (GICs) have precise indication for these cases. Moreover, the use of a GIC base underneath composite resin, the so-called "sandwich" or mixed technique, allows associating the good characteristics of composite resins and GICs, and has been considered quite useful in the restoration of non-carious cervical defects. The aim of this paper is to critically review the literature and discuss peculiar features of GICs regarding their role in the restoration of non-carious cervical lesions.