RESUMEN
With the increase in the population's life expectancy, there has also been an increase in the rate of osteoporosis, which has expanded the search for strategies to regenerate bone tissue. The ultrasonic sonochemical technique was chosen for the functionalization of the 45S5 bioglass. The samples after the sonochemical process were divided into (a) functionalized bioglass (BG) and (b) functionalized bioglass with 10% teriparatide (BGT). Isolated mesenchymal cells (hMSC) from femurs of ovariectomized rats were differentiated into osteoblasts and submitted to in vitro tests. Bilateral ovariectomy (OVX) and sham ovariectomy (Sham) surgeries were performed in fifty-five female Wistar rats. After a period of 60 days, critical bone defects of 5.0 mm were created in the calvaria of these animals. For biomechanical evaluation, critical bone defects of 3.0 mm were performed in the tibias of some of these rats. The groups were divided into the clot (control) group, the BG group, and the BGT group. After the sonochemical process, the samples showed modified chemical topographic and morphological characteristics, indicating that the surface was chemically altered by the functionalization of the particles. The cell environment was conducive to cell adhesion and differentiation, and the BG and BGT groups did not show cytotoxicity. In addition, the experimental groups exhibited characteristics of new bone formation with the presence of bone tissue in both periods, with the BGT group and the OVX group statistically differing from the other groups (p < 0.05) in both periods. Local treatment with the drug teriparatide in ovariectomized animals promoted positive effects on bone tissue, and longitudinal studies should be carried out to provide additional information on the biological performance of the mutual action between the bioglass and the release of the drug teriparatide.
RESUMEN
The present study evaluated the effect of glass application with and without silver-doped soda-lime glass on roughness, biofilm formation, cell viability and flexural strength of a zirconia. Samples of 3-YTZP (3 mol% yttria stabilized tetragonal zirconia polycrystals) were divided into: polished (P); glaze (G); glass infiltration (INF); 4% silver-doped soda-lime glass (Ag4); glass infiltration + 4% silver-doped soda-lime glass (INF-Ag4); 5% silver-doped soda-lime glass (Ag5); glass infiltration + 5% silver-doped soda-lime glass (INF-Ag5). Samples were submitted to the following analyses: roughness (Ra); free surface energy (FSE); colony-forming units count (log CFU/mL); scanning electron microscopy (SEM); cytotoxicity (MTT assay) and flexural strength. Ag5 had greater roughness and FSE, but less biofilm adherence. In the CFU, silver-doped soda-lime glass groups inhibited the growth of Candida albicans, while the Ag5 inhibited Streptococcus mutans and none of the groups was effective against Streptococcus sanguinis. In the qualitative evaluation, lower number of colonies in the Ag5 grew up, compared to the control groups (P; G and INF) for both C. albicans and S. mutans. Regarding the MTT assay, the Ag4, INF-Ag4 and INF-Ag5 obtained percentage of cell viability greater than 50%. Ag5 showed lower flexural strength when compared to the control groups, while the application of glass infiltration increased the flexural strength by formation of a graded region between zirconia-glass. In conclusion, Ag5 had the greatest antimicrobial effect, Ag4 and INF-Ag4 were the less cytotoxic and the INF was the most resistant to fracture. Therefore, INF-Ag4 conciliates the best performance in terms of antimicrobial and mechanical properties for a 3-YTZP.