In Vivo Biocompatibility, Mechanical, and Antibacterial Properties of Cements Modified with Propolis in Different Concentrations

Objectives The focus of this triple-blind randomized study was to evaluate the mechanical properties, antibacterial effect, and in vivo biocompatibility of glass ionomer cements (GICs) modified with ethanolic extracts of propolis (EEP). Materials and Methods For biocompatibility tests, 135 male Wistar rats were used and divided into nine groups: Group C (control, polyethylene), Groups M, M10, M25, M50 (Meron; conventional, and modified with 10%, 25%, 50% EEP, respectively), Groups KC, KC10, KC25, KC50 (Ketac Cem; conventional, and modified with 10%, 25%, 50% EEP, respectively). The tissues were analyzed under an optical microscope for different cellular events in different time intervals. Shear bond strength test (SBST) on cementation of metal matrices ( n = 10, per group), adhesive remnant index (ARI) in bovine incisors ( n = 10, per group), and antibacterial properties by the agar diffusion test ( n = 15, per group) were analyzed. Statistical Analysis Data were analyzed by Kruskal–Wallis test followed by Dunn, and one-way analysis of variance test followed by Tukey’s test ( p < 0.5). Results Morphological evaluation demonstrated intense inflammatory infiltrate in Groups M10 and KC10 in the time intervals of 7 ( p = 0.001) and 15 ( p = 0.006) days. Multinucleated giant cells were shown to be more present in Group M1, with statistical difference from Control and KC50 Groups in the time interval of 7 days ( p = 0.033). The SBST showed no statistical significance among the groups ( p > 0.05). Antibacterial property showed a statistically significant difference between Meron and Meron 50%-EEP Groups, and between Ketac and Ketac 50%-EPP Groups ( p = 0.001). Conclusions The intensity of histological changes resulting from the cements was shown to be inversely proportional to the concentration of propolis added; Ketac 50%-EPP was the concentration that had the most favorable biocompatibility results. Addition of EEP to GIC did not negatively change the SBST and ARI. Antibacterial property demonstrated a concentration-dependent effect.