SUMMARYThis study evaluated the importance of the union between dentin collagen and three different adhesive materials. Sixty Class V restorations were prepared on the buccal and lingual surfaces of 30 recently extracted human premolars, with the cervical margins in dentin and the occlusal margins in enamel. These restorations were distributed to three groups of 20 cavities each based on the employed adhesive system used: Group A: Single Bond; Group B: Prime&Bond NT; Group C: One Coat Bond. Each group was subdivided according to dentin treatment: 1) manufacturers' adhesive protocol and 2) removal of the collagens fibers (total etch + sodium hypochlorite 5% for two minutes) + adhesive protocol. After the restorations were completed, the teeth were stored in saline solution (24 hours/37°C), subjected to thermal cycling, washing and scoring according to dye penetration. Dye penetration was evaluated, with the numbers ranging from 0 (no infiltration) to 3 (greatest infiltration). WhenThe results of this research showed that, with regard to marginal seal, collagen fibrils were not essential to obtaining an optimal adhesive performance. Deproteinization should be considered as a bonding pre-treatment.

Self-adhesive resin cements represents a new approach in indirect restorative dentistry, although little is known about its biological properties. The influence of the curing strategy on the biological response of a self-adhesive resin cement (Rely-X Unicem/3M ESPE) was evaluated through methyltetrazolium (MTT) and nitric oxide (NOx) assays. Cylindrical specimens (n = 48) were prepared and cured according to the following strategies: photoactivation with halogen light-curing unit (LCU) Demetron/Kerr, LED LCU Radii/SDI, and chemical activation. A control group with culture medium and a group with lipopolysaccharide, employed for cells stimulation, were used for comparisons (n = 8). After 24 h of direct contact between specimens and rat alveolar macrophages, the biological response was evaluated. Statistical evaluation of the data was performed with Kruskal-Wallis and Dunn's test (p = 0.05). The MTT test showed that the specimens cured by halogen light and chemical activation provided higher alterations on cell metabolism. For LED-cured specimens, cell viability was compatible to the results observed in the control group. For the NOx assay, all curing methods were cytotoxic to rat macrophages. Rely-X Unicem demonstrated different cytotoxic effects according to the curing strategy employed.

Deproteinization has been shown to optimize dentin bonding, but differences in adhesive composition should be considered. The objective of this study was to evaluate the effect of dentin deproteinization on microtensile bond strength (microTBS) of four total-etch adhesive systems (Single Bond/SB, Prime & Bond NT/PB, One Coat Bond/OC, and PQ1/PQ). The ultrastructure of the resin-dentin interfaces was also examined using scanning electron microscopy. Tukey's multiple-comparison tests indicated that PB and PQ produced significantly higher microTBS (p<0.05) after dentin deproteinization (PB=61.53 MPa, PQ=58.18 MPa). This treatment provided statistically lower results for SB (39.08 MPa), but the microTBS of OC to dentin was unaffected by dentin deproteinization. The bonding performance on deproteinized dentin surfaces depended on the characteristics of each adhesive system, as well as the adhesive dentin specificity to the oxidant effect of sodium hypochlorite. Incorporation of fillers in the adhesive, a possible self-etching action, and the presence of a volatile solvent (acetone) were the main factors for a better union between the adhesive system and deproteinized substrate.

O estágio curricular supervisionado nos serviços públicos de saúde, tal qual recomendado pelas Diretrizes Curriculares Nacionais (DCN), possibilita aos estudantes de Odontologia a proximidade com realidades e condutas profissionais diferentes daquelas que caracterizam sua rotina na prática clínica intramuros. O objetivo deste estudo foi realizar uma revisão da literatura sobre os estágios curriculares dos cursos de Odontologia nos serviços públicos de saúde brasileiros após as DCN publicadas em fevereiro de 2002 e assim estimular a reflexão sobre sua importância para a formação profissional contemporânea. Foi realizada uma revisão de literatura narrativa, baseada nos dados obtidos a partir da consulta em bases de dados (PubMed, SciELO, LILACS e Google Acadêmico), selecionando documentos publicados entre janeiro de 2010 e maio de 2017. A amostra final foi constituída por 15 publicações agrupadas nas seguintes categorias: relatos de experiência vivenciada no estágio curricular, percepção dos estudantes quanto ao estágio curricular e avaliação dos processos pedagógicos, técnicos e políticos na implantação do estágio. Conclui-se que os estágios curriculares das universidades brasileiras são espaços de aprofundamento no campo de trabalho que buscam aproximar os estudantes da realidade do sistema público de saúde, com intenção de formar profissionais humanitários, preocupados com o respeito e o cuidado da sociedade.