IADR Abstract Archives
Bioactive Glass-Functionalized Composites: 1-Year Bond Strength With a Universal Adhesive
Objectives: To evaluate the dentin bond strength of experimental resin composites functionalized with an F-containing bioactive glass (BG) after simulated aging for 1 year in vitro.
Methods: Experimental composites were prepared using a light-curable bis-GMA/TEGDMA resin matrix (60:40 by weight), 10–40 wt% of a low-Na F-containing BG, and reinforcing fillers (micro-sized barium glass and nano-sized silica). The total filler content was 70 wt%. The reference composite was prepared with reinforcing fillers only, and a giomer was used as a commercial reference material. The substrates for bonding were prepared from mid-coronal dentin, a universal adhesive was applied in self-etch mode, and composite cylinders (diameter=3.1 mm, height=3 mm) were bonded in two 1.5-mm increments (cured separately). Three subgroups of test specimens were prepared for aging over 1, 6, and 12 months. A total of 270 specimens were tested (5 materials x 3 time points x 18 specimens per experimental group). The bond strength was tested in macro-shear mode using a universal testing device at a crosshead speed of 0.5 mm/min until failure. Bond strength values were compared with the Kruskal-Wallis test and Bonferroni post-hoc adjustment.
Results: Median bond strength values at baseline (1 month) were 25–32 MPa and were statistically similar for all materials. After 6 months, no statistically significant change in bond strength was observed with median values in the range of 23–26 MPa. After 1 year, all experimental composites showed a significant increase in bond strength compared to the 6-month values, with median values of 30–36 MPa. The 1-year bond strength of all BG-containing composites was statistically similar to that of the experimental reference material and the commercial reference material (giomer).
Conclusions: Functionalizing experimental composites with 10–40 wt% BG showed no adverse effects on their dentin bond strength after 1 year.
Methods: Experimental composites were prepared using a light-curable bis-GMA/TEGDMA resin matrix (60:40 by weight), 10–40 wt% of a low-Na F-containing BG, and reinforcing fillers (micro-sized barium glass and nano-sized silica). The total filler content was 70 wt%. The reference composite was prepared with reinforcing fillers only, and a giomer was used as a commercial reference material. The substrates for bonding were prepared from mid-coronal dentin, a universal adhesive was applied in self-etch mode, and composite cylinders (diameter=3.1 mm, height=3 mm) were bonded in two 1.5-mm increments (cured separately). Three subgroups of test specimens were prepared for aging over 1, 6, and 12 months. A total of 270 specimens were tested (5 materials x 3 time points x 18 specimens per experimental group). The bond strength was tested in macro-shear mode using a universal testing device at a crosshead speed of 0.5 mm/min until failure. Bond strength values were compared with the Kruskal-Wallis test and Bonferroni post-hoc adjustment.
Results: Median bond strength values at baseline (1 month) were 25–32 MPa and were statistically similar for all materials. After 6 months, no statistically significant change in bond strength was observed with median values in the range of 23–26 MPa. After 1 year, all experimental composites showed a significant increase in bond strength compared to the 6-month values, with median values of 30–36 MPa. The 1-year bond strength of all BG-containing composites was statistically similar to that of the experimental reference material and the commercial reference material (giomer).
Conclusions: Functionalizing experimental composites with 10–40 wt% BG showed no adverse effects on their dentin bond strength after 1 year.