Interleukin-1 beta and interleukin-8 in healthy and inflamed dental pulps

After aggression to the dental pulp, some cells produce cytokines in order to start and control the inflammatory process. Among these cytokines, interleukin-1 beta (IL-1β) and interleukin-8 (IL-8) emerge as important ones. OBJECTIVE: The purpose of this study was to analyze the location, distribution and concentration of these cytokines in healthy and inflamed dental pulps. MATERIAL AND METHODS: Twenty pulps, obtained from healthy third molars (n=10) and from pulpectomies (n=10) were used for the study, with half of each group used for immunohistochemistry and half for protein extraction and ELISA assays. Fibroblasts obtained from healthy dental pulps, stimulated or not by Escherichia coli lipopolysaccharide (LPS), in order to simulate aggression on the cell cultures, were also used and analyzed by ELISA for IL-1β and IL-8 as complementary information. Data obtained from immunohistochemistry were qualitatively analyzed. Data obtained from ELISA assays (tissue and cells) were statistically treated by the t-test (p<0.05). RESULTS: Immunohistochemically, it was observed that inflamed pulps were strongly stained for both cytokines in inflammatory cells, while healthy pulps were not immunolabeled. ELISA from tissues quantitatively confirmed the higher presence of both cytokines. Additionally, cultured pulp fibroblasts stimulated by LPS also produce more cytokines than the control cells. CONCLUSIONS: It may be concluded that inflamed pulps present higher amounts of IL-1β and IL-8 than healthy pulps and that pulp fibroblasts stimulated by bacterial LPS produce higher levels of IL-1β and IL-8 than the control group.

Biocompatibility of two types of resins for prosthetic usage/Biocompatibilidade de dois tipos de resina para uso protético

The purpose of the present study was evaluate the biological compatibility of materials used to manufacture prostheticappliances. A heat-polymerized colorless resin and one visible light-cured denture base material were tested by the implantation of probe discs, in the dorsal connective tissue of 12 Wistar rats. The animals were sacrificed at 7, 14, 21 and 28 days after implantation. The specimens were prepared for light microscopy observation. It was noted that either after light microscopy observations, both resins demonstrated a good level of biocompatibility within the connective tissue of the dorsum of the animals studied.

O objetivo deste trabalho foi avaliar a compatibilidade de biológica de materiais usados na confecção de aparelhosprotéticos. Foram testadas uma resina incolor ativada termicamente e uma resina rosa ativada por luz visível. Discosdestas resinas foram implantados no tecido conjuntivo do dorso de 12 ratos Wistar. Os animais foram sacrificados em 7,14, 21 e 28 dias após a implantação. Os cortes foram preparados para observação em microscopia de luz. Observou-seque as duas resinas demonstraram bom nível de compatibilidade no tecido conjuntivo.

O uso de microondas para descalcificaçäo de tecidos mineralizados da mandíbula de ratos / Using microwaves for the decalcification of mineralized tissues of the rat mandible

Neste trabalho, compararam-se a preservaçäo tecidual e o tempo de descalcificaçäo através de E.D.T.A. a 7 por cento, pH 7,3, hemimandíbulas de ratos fixadas em etanol 70 por cento, associado ou näo às microondas. Houve o mesmo grau de preservaçäo histológica em ambos os grupos estudados, com uma acentuada reduçäo do tempo de desmineralizaçäo na ordem de 83 por cento quando se associou o microondas