IADR Abstract Archives
Bond Strength of a Flowable Bulk-fill Resin Composite in MOD Cavities After Chewing Simulation
Objectives: To evaluate the microtensile bond strength (µTBS), after chewing simulation, of a bulk-fill flowable base composite to dentin from gingival walls of Class II MOD cavities, when the incremental or bulk filling technique was performed.
Methods: Class II MOD cavities were prepared in 36 human molars with the distal and mesial proximal boxes depth of 4 or 6 mm, respectively. Eight experimental groups (n=9) were obtained by a factorial design including “composite” in two levels, a bulk-fill low-stress composite (SDR- SureFil SDR Flow, Dentsply Caulk) and a Conventional composite (EXH- Esthet-X HD, Dentsply Caulk); “Filling Technique” in two levels: Bulk-filling (BF) and Incremental (IN); and “depth” in two levels: 4 mm and 6 mm in order to create different polymerization conditions. 24 h after placement of restorations teeth were submitted to a thermomechanical challenge in a chewing simulator, with 5x105 cycles. After, teeth were sectioned into beams with a cross-sectional bonded area of approximately 1 mm2. Bonded beams obtained from the gingival walls of the proximal boxes were tested in tension with a crosshead speed of 1 mm/min. Data were submitted to a 3-way ANOVA followed by post hoc Tukey test (p<0.05).
Results: ANOVA failed to identify significant differences for the triple and double interaction between factors. However, significant differences were observed for the factors “Composite” and “Filling technique” (p<0.05). SDR presented significantly higher μTBS values for bulk and incremental filling techniques (SDR= 57.3 [2.2]A; EXH= 50.07 [2.3]B), and the incremental filling technique presented significantly higher μTBS values for both composites (BF= 49.8 [2.3]b; IN= 57.59 [2.2]a).
Conclusions: It can be concluded that the bulk-fill flowable composite SDR may improve the bond strength to the gingival walls of Class II MOD cavities.
Methods: Class II MOD cavities were prepared in 36 human molars with the distal and mesial proximal boxes depth of 4 or 6 mm, respectively. Eight experimental groups (n=9) were obtained by a factorial design including “composite” in two levels, a bulk-fill low-stress composite (SDR- SureFil SDR Flow, Dentsply Caulk) and a Conventional composite (EXH- Esthet-X HD, Dentsply Caulk); “Filling Technique” in two levels: Bulk-filling (BF) and Incremental (IN); and “depth” in two levels: 4 mm and 6 mm in order to create different polymerization conditions. 24 h after placement of restorations teeth were submitted to a thermomechanical challenge in a chewing simulator, with 5x105 cycles. After, teeth were sectioned into beams with a cross-sectional bonded area of approximately 1 mm2. Bonded beams obtained from the gingival walls of the proximal boxes were tested in tension with a crosshead speed of 1 mm/min. Data were submitted to a 3-way ANOVA followed by post hoc Tukey test (p<0.05).
Results: ANOVA failed to identify significant differences for the triple and double interaction between factors. However, significant differences were observed for the factors “Composite” and “Filling technique” (p<0.05). SDR presented significantly higher μTBS values for bulk and incremental filling techniques (SDR= 57.3 [2.2]A; EXH= 50.07 [2.3]B), and the incremental filling technique presented significantly higher μTBS values for both composites (BF= 49.8 [2.3]b; IN= 57.59 [2.2]a).
Conclusions: It can be concluded that the bulk-fill flowable composite SDR may improve the bond strength to the gingival walls of Class II MOD cavities.