IADR Abstract Archives
Mechanical Properties of Fiber-reinforced Provisional C&B Materials and Thermocycling Effects
Objectives: To assess the reinforcement effect of incorporating glass-fibers on flexural strength and flexural modulus of crown and bridge provisional restorative materials with thermocycling treatment.
Methods: Two commercially available light-curing unidirectional glass-fibers, were tested: Dentapreg (ADM), and everStick®C&B(GC) in combination with 2 self-curing provisional C&B materials: PMMA (Coldpac, Yates Motloid) and Bis-acrylic(Protemp Plus, 3M). Rectangular specimens measuring 3×3×24mm were fabricated using customized aluminum molds in the following six groups (n=20/group): A. Coldpac; B. Coldpac with Dentapreg; C. Coldpack with everStick®C&B; D. Protemp; E. Protemp with Dentapreg; F. Protemp with everStick®C&B. For each reinforced specimen, the provisional material was applied into the bottom 1/3 of the mold. A coating of bonding agent and 24mm fiber were placed and cured for 5 seconds by Bluphase16i (Ivoclar). Another coating of adhesive was applied on the fiber and the remaining 2/3 of the mold was filled with the provisional material, then cured for 40 seconds. Each group was further divided in two subgroups (n=10/group) for water storage (37oC, 72hrs) and thermocycling (5-55oC, 3000 cycles, TC). All specimens were then subjected to a three-point bending test (Instron 5566A). Flexural strength and flexural modulus data were analyzed via one-way ANOVA using SAS JMP12.
Results: Flexural strength and flexural modulus of tested materials are shown in the bar charts below.
Conclusions: The fiber-reinforced groups demonstrated significantly higher flexural strength and flexural modulus than non-reinforced groups (p< 0.001). Water storage and thermocycling had no significant effect on the flexural strengths in all groups. No significant difference was found between the reinforcement effects of Dentapreg and everStick®C&B (p =0.275). Thermocycling had a significant effect of lowering the flexural modulus of Protemp-Plus with Dentapreg (p=0.0046).
Methods: Two commercially available light-curing unidirectional glass-fibers, were tested: Dentapreg (ADM), and everStick®C&B(GC) in combination with 2 self-curing provisional C&B materials: PMMA (Coldpac, Yates Motloid) and Bis-acrylic(Protemp Plus, 3M). Rectangular specimens measuring 3×3×24mm were fabricated using customized aluminum molds in the following six groups (n=20/group): A. Coldpac; B. Coldpac with Dentapreg; C. Coldpack with everStick®C&B; D. Protemp; E. Protemp with Dentapreg; F. Protemp with everStick®C&B. For each reinforced specimen, the provisional material was applied into the bottom 1/3 of the mold. A coating of bonding agent and 24mm fiber were placed and cured for 5 seconds by Bluphase16i (Ivoclar). Another coating of adhesive was applied on the fiber and the remaining 2/3 of the mold was filled with the provisional material, then cured for 40 seconds. Each group was further divided in two subgroups (n=10/group) for water storage (37oC, 72hrs) and thermocycling (5-55oC, 3000 cycles, TC). All specimens were then subjected to a three-point bending test (Instron 5566A). Flexural strength and flexural modulus data were analyzed via one-way ANOVA using SAS JMP12.
Results: Flexural strength and flexural modulus of tested materials are shown in the bar charts below.
Conclusions: The fiber-reinforced groups demonstrated significantly higher flexural strength and flexural modulus than non-reinforced groups (p< 0.001). Water storage and thermocycling had no significant effect on the flexural strengths in all groups. No significant difference was found between the reinforcement effects of Dentapreg and everStick®C&B (p =0.275). Thermocycling had a significant effect of lowering the flexural modulus of Protemp-Plus with Dentapreg (p=0.0046).
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