Biomechanical and Chemical Behavior of Various Bioactive Materials in Class II Restorations

The aim of this in vitro study was to evaluate the biomechanical and chemical behavior of various bioactive materials in class II MOD restorations. Forty-eight standardized class II MOD cavities were prepared in sound extracted human molar teeth.  The specimens were divided into four groups according to the restorative material: Group 1 (Filtek™ Z350 XT), Group 2 (Biodentine™ as a liner, and then restored with Filtek™ Z350 XT), Group 3 (Cention N™), and Group 4 (Activa™ Bioactive-Restorative). The samples were tested for fracture resistance by subjecting them to a compressive load in a Universal testing Machine. The failure modes of each specimen were evaluated. The alkalinizing potential and calcium ion release of the materials were measured. SEM-EDAX analyses were also performed for all materials. Data were analyzed using ANOVA and post hoc Tukey test (p<0.05). Group 1 showed the higher fracture resistance (p<0.05). Group 3 had greater fracture resistance values but no statistical difference from Group 4. Biodentine™ showed greater biomineralization potential. Class II MOD restorations of Group 1 displayed the higher fracture resistance; however, it was highly associated with catastrophic failure. Conversely, Biodentine™ presented a more significant bioactivity potential, and its use, as in Group 2, promoted the most favorable failure mode.