Immediate and Long Term Gingival Marginal Leakage of Two Bioactive Bulk Fill Restorative Materials (A Comparative in vitro Study)
Objective: The aim of this study was to examine Immediate and long term gingival marginal leakage of two bioactive restorative materials in cl II cavity preparations. Materials and methods: Forty eight maxillary first premolar teeth of comparable sizes were collected and allocated into three main groups according to the restorative materials used (n=16): Group (A): Filtek™ Bulk Fill, Group (B): Predicta™bulk bioactive composite, Group (C): ACTIVA™ bioactive composite. Two slot cavities, with standardized dimensions, were prepared in each tooth (3mm buccolingual, 2mm mesiodistal, and mesial gingival margin located 1mm coronal to CEJ and distal gingival margin located 1mm apical to CEJ (.All groups were further divided into two subgroups according to the storage periods: subgroup1 (n=8) the teeth were stored for 24 hours, while in subgroup2 (n=8) for 90 days in SBF as storage medium. The restored samples were thermo cycled and then immersed in methylene blue dye (2%) for 24 hours. Dye diffusion was evaluated by inspect the sectioned samples using digital microscope at 40× magnification. Statistical Analysis: The data were analyzed using Kruskal-Wallis test and Mann-Whitney U-test. Results: The results showed statistically insignificant differences among the restorative materials at 24 hours. However, after 90 days storage the differences were statistically significant, Predicta™ showed lowest microleakage followed by Filtek™ bulk fill while ACTIVA™ showed the highest microleakage. Conclusions: all tested restorative materials showed increase microleakage after aging, dentin margin revealed greater microleakage than enamel.