Method: Green propolis - GP (Propolis Pharmanéctar, Belo Horizonte) was incorporated into the powder of restorative GIC (MaxxionR, FGM, color A2). This combined powder (CP) presented 0.4g of GP lyophilized in 1.6 g of GIC powder (ratio of 20%). Twenty specimens were prepared and divided into two groups (n=10). Group A: CP + GIC liquid, group B: CP + GIC liquid + surfactant (0.04mL of 50% alcohol). Following final cure, specimens measurements were recorded using a digital balance 10-4g precision and final mass was standardized (0,100g). GIC specimens according the pattern of each group without addition of propolis were used as negative control. Pure GP was positive control. Dilution of GP was performed in water-alcohol solution until 0.02g/l concentration, for spectroscopy calibration. The release of propolis was measured at 1h, 2h, 4h, 24h, 7, 15 and 30 days using spectrophotometer (wavelength 300nm). The results were subjected to analysis of variance (p=0.05).
Result: Propolis average release was significantly higher at period of 24h (group A: 166.6µg, group B: 118.9µg) and 7 days (group A: 134.4µg, group B: 168μg) comparing with others evaluated periods. There was no significant difference between these periods for both groups. At 1h, 14 and 30 days release was not statistically different and was significantly higher than at 2h and 4h.
Conclusion: Propolis incorporated into GIC powder was released for both groups, and the surfactant alters the pattern.