SUMMARY

Clinical RelevanceThe results of this study suggest that the evaluated resin-modified glass ionomer cement and resin cement will increase the marginal discrepancy after cementation of the evaluated ceramics. SUMMARYStatement of the Problem: Full-coverage allceramic restorations are widely used. The impact of various classifications of luting agent on marginal discrepancies is not well understood.Purpose: The purpose of this study was to evaluate the cervical fit of all ceramic crowns (IPS e.maxPress, Cergogold, and In Ceram) on bovine teeth with two luting agents before and after cementation. Materials and Methods: Ninety bovine incisors were embedded in resin. The coronal portions of the teeth were prepared to receive fullcoverage crowns. Thirty crowns of 7.0 6 0.5 mm height, 8.0 mm cervical diameter, and 4.2 mm incisal diameter were fabricated for each ceramic system. The crowns were seated on the teeth, and the marginal discrepancy was measured using a measuring microscope. Then, 15 crowns of each ceramic system were luted on the teeth with resin cement (Variolink II) or resin-modified glass ionomer cement (Rely X luting), and the marginal discrepancy was measured. The results were submitted to analysis of variance, t test and Tukey's test (p,0.05).Results: The three ceramic systems showed cervical fits after cementation statistically

-Background -Proton-pump inhibitors have been used for at least two decades. They are among the most commonly sold drugs in the world. However, some controversy remains about the indications for their use and the consequences of their prolonged use. Objectives -To evaluate and compare the endoscopic and histopathologic gastric changes in chronic users of proton-pump inhibitors to changes in non-users. Methods -A prospective study performed at a tertiary Public Hospital involving 105 patients undergoing upper-gastrointestinal endoscopy. Subjects included 81 proton-pump inhibitor users and 24 non-users (control group).Biopsies of the antral-type mucosa, the antral-fundic transition, and the fundus were evaluated by the Sydney System. The presence of erosion or ulceration, lymphatic follicles, reactive gastropathy, and polypoid or epithelial hyperplasia was also determined. Serum levels of gastrin were measured. Results -We found two polyps, one in each group, both of which were negative for Helicobacter pylori. There were two cases of parietal cell hyperplasia in users of proton-pump inhibitors. Gastrin was elevated in 28 users of proton-pump inhibitors and in four members of the control group. We did not find statistically significant differences in the endoscopic or histopathologic findings between the two groups. Conclusion -Chronic use of proton-pump inhibitors for the duration examined was not associated with significant gastric changes. An interesting finding was that the 4 chronic users of proton-pump inhibitors who had serum gastrin levels above 500 pg/mL also had positive serology for Chagas disease.

The aim was to evaluate the influence of different dentin preparation mode in the smear layer characteristics (SL), hybrid layer (HL), and microtensile bond strength (µTBS) to dentin with two resin cements. The occlusal dentin of 120 third molars was exposed. The teeth were divided into 4 groups (n=30) according to the dentin preparation mode: 1- fine grain diamond bur; 2- coarse grain diamond bur; 3- multi laminate carbide steel bur; and, 4- ultrasonic CV Dentus diamond bur. Each treated dentin group was divided into 2 sub-groups (n=15) according to the resin cement: (1) RelyX U200 and (2) RelyX ARC. Resin composite blocks were cemented on dentin. After storage at 37o C for 24 h, beams with a cross section area of 1.0 mm2 were obtained, and tested in a universal testing machine at a crosshead speed of 0.5 mm/min. Two additional teeth for each sub-group were prepared to analyze the SL and HL on a scanning electron microscopy. According to Kruskal-Wallis test and Dunn tests, there was no significant difference in µTBS among the rotary instruments within each resin cement group. RelyX ARC obtained higher µTBS values compared to RelyX U200 (p<0.05). RelyX ARC formed evident HL, which was not observed for RelyX U200. The dentin mode preparation did not influence the µTBS of the resin cements. The SL was different for all instruments. The cementing agent is more determinant in the hybrid layer formation and bond strength to dentin than the instruments applied on dentin.

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Lesões cervicais não cariosas (LCNC) estão entre as situações mais frequentes que afetam as estruturas dentais, e embora a restauração com resinas compostas não trate diretamente a etiologia dessa condição, ela substitui o tecido dental perdido e recupera a integridade estrutural dos dentes. O tratamento restaurador contribui também na redução do desgaste dental e da hipersensibilidade dentinária, quando presente, além de melhorar a estética. Apesar dos benefícios brevemente apresentados, a longevidade das restaurações em LCNC ainda é um problema nos dias atuais devido a problemas relacionados à retenção do material nas cavidades. Esse estudo teve como objetivo avaliar se diferentes métodos de fotoativação interferem na longevidade dessas restaurações. Portanto, foram coletadas informações de artigos científicos, trabalhos de conclusão de curso e dissertações de mestrado em bases de dados online, além de capítulos de livros relacionados ao tema da pesquisa. Foi então realizada uma discussão das diferentes técnicas de fotoativação e intensidades de luz, comparando-se os efeitos positivos e negativos em relação à microinfiltração e à adaptação marginal, assim como vantagens e desvantagens a fim de promover resultados satisfatórios a longo prazo das restaurações em LCNC.