Bioactive Materials including glass and glass-ceramics are nowadays used as medical implants for orthopedic applications. In this study several samples of glass-ceramics have been prepared using both heat treatment and sol-gel processes. The structure and bioactivity of these samples based on their interaction with simulated body fluid (SBF) have been determined, invitro, using the Raman spectroscopic technique. It is found that most samples exhibit bioactivity when they are soaked in SBF. It is also concluded that Raman spectroscopy is a powerful technique in such studies.

Introduction: The use of Bioactive glasses to re-establish or increase mechanical properties of the root dentin may be an interesting alternative. The aim of this study was to evaluate the effect of root repair Materials and Bioactive glasses on the microhardness of human root dentin. Methods and Materials: Sixty-four sectioned palatal roots of human molars were prepared and two slices were obtained of the middle third of each root (one corresponding to the control group, without treatment, and the other to the experimental group). The pairs of slices were randomly divided into four groups (n=16). The root canal of experimental slices were filled with one of the following Materials: mineral trioxide aggregate (Angelus MTA, Angelus, Londrina, Paraná , Brazil), EndoSequence Root Repair Material (ERRM, Brassler, Savannah, GA, USA), Bioglass (45S5) and an experimental niobophosphate glass (NbG). The specimens were stored in an oven at 37º C, in an environment with 100% humidity for 60 days. The specimens were subjected to a microhardness test. Four indentations were made at a distance of 20 μ m from the root canal lumen. For microhardness analysis, comparing the experimental groups and their respective controls, the Student’ s-t test was applied. For comparison of the percentage increase in microhardness between the groups, the data were statistically analyzed by using One-way ANOVA and Tukey’ s test. The level of significance was set at 0. 05. Results: All the Materials significantly increased the dentin microhardness values (P<0. 05). MTA showed a higher increase in microhardness (94. 8± 42. 7%), similar to that of EndoSequence (62. 3± 39. 9%). The 45S5 (46. 5± 30. 0%) and NbG (53. 8± 31. 3%) showed the lowest percentages of increase in microhardness, but were statistically similar to those of EndoSequence. Conclusion: All the Materials tested were capable of increasing root dentin microhardness.