Apatite Forming Ability and Gingival Marginal Adaptation of Two Bioactive Bulkfill Composite Restorative Materials (An in vitro comparative study)

Aims: The present study aimed to assess the apatite-forming ability and marginal adaptation of two bioactive bulkfill restorative materials in Cl. II cavities after storage in phosphate-buffered saline (PBS). Materials and Methods: Sixteen sound molars with nearly equivalent occlusal size were molded into a PVC tube, then divided into four groups (n=4) based on composite material types. Each tooth received two separate MO and DO cavity preparations, cavity restorations, and thermocycling, then stored for 28 days in PBS. After that, all the teeth samples were sent for FESEM/EDX analyses. Statistical analyses were performed using One-Way ANOVA and Duncan's Multiple Range test to evaluate and compare the results at a 5% significant level. Result: According to the study, there was a statistically significant difference at (P≤0.05) among the groups in terms of gap width formation in µm at restorative materials-gingival enamel margin interfaces. Group B: Ever X Posterior represented the highest mean of gap width (13.05 ± 3.68), followed by group D: Predicta bioactive (7.86 ± 1.22) and group C: Cention N (7.50 ± 1.09), while group A: Tetric powerFill represented the lowest mean of gap width (6.50 ± 1.61). The FESEM images for bioactive materials represented the apatite deposition, and these results were confirmed with the EDX compositional elements analytical results. Conclusion: The gingival marginal adaptation of Cl. II cavities can be affected by the composition and the properties of the composite materials used. The bioactive restorative materials are considered promising materials with clinical beneficial effect.