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The objective of this study was to evaluate the influence of a cola soft drink (CSD) and coffee on the microhardness and surface roughness of composite resin. Fifty cavities were prepared on the vestibular surface of bovine incisors and restored with nanoparticulate resin. The teeth were divided into five groups (n = 10): group A (control), immersion in artificial saliva (AS) for 14 days; group B, immersion in coffee for 15 min (3×/day) for 7 days followed by immersion in AS for another 7 days; group C, immersion in CSD for 15 min (3×/day) for 7 days followed by immersion in AS for another 7 days; group D, immersion in AS for 7 days, immersion in coffee for 15 min (3×/day) for 7 days; group E, immersion in AS for 7 days, immersion in CSD for 15 min (3×/day) for 7 days. After the immersion periods the specimens were analyzed for their microhardness and surface roughness. The data were subjected to analysis of variance (ANOVA) followed by t-test with 5% significance. Group A presented the highest average microhardness and lowest surface roughness, so it was possible to conclude that the consumption of CSD and coffee alters the microhardness and surface roughness of new restorations.

Objective: This clinical case report addresses the step-by-step of the application of a core-and-post system that uses a single resin composite material to fiber post cementation and core build-up in a maxillary left central incisor.Clinical considerations: The literature reports several materials and methods for the restoration of endodontically treated teeth with coronal destruction that require an intra-radicular fiber post for the core build-up. The present case report describes a core-and-post or "monoblock" technique. A dual resin composite (Core-X Flow;Dentsply DeTrey) highly filled material and cement was used for luting the fiber post (Blue X-Post) and build-up the core structure in an easy application. Conclusions:The "core-and-post" technique that uses a single material system protocol minimizes the material interfaces, steps of procedures, and chair-time in comparison to conventional techniques.Clinical Significance: The use of different materials for post cementation and core build-up requires more steps, which increases the chair-time and number of interfaces among the materials. Since the "monoblock" technique uses only one material, it can streamline the clinical procedures, thus, saving time and materials. Moreover, techniques based on core-and-post systems are easily applied, versatile, and esthetics, and can be applicable to posterior and anterior teeth.