IADR Abstract Archives
Mechanical properties, fracture resistance and fatigue limits of short fiber composite
Objectives: The aims of this study were firstly to determine the fracture resistance and the compressive fatigue limit (CFL) of anterior crown restorations made of short-fiber reinforced composite (SFC) and secondly to investigate selected mechanical properties of the material following standards and observe their correlation with the CFL.
Methods: Ten specimens/group were fabricated either from SFC (everX Posterior, GC) or particulate filler composite (PFC;G-ænialAnterior, GC). Investigated properties were flexural strength (FS), compression strength (CS), diametral-tensile strength (DTS) and single-edge-notched-bend fracture toughness (FT) following ISO standards. Fracture resistance was determined by static load (n=10/group) and the CFL at 10 000 cycles was determined using a staircase approach (n=20/group), both on anterior composite crowns. All results were statistically analysed with analysis of variance (ANOVA) followed by Turkey post hoc test and Pearson-correlation analysis.
Results: ANOVA revealed that restorations made from SFC had higher fracture resistance (954±121N) and CFL (267±23N) (p<0.05) than the PFC. SFC revealed also higher FT (2.60 MPa·m1/2) than the PFC (1.0 MPa·m1/2). From the mechanical tests investigated, strong correlation was observed only between the FT and the CFL (r2=0.899; p <0.05).
Conclusions: Restorations made from SFC revealed promising performance under high static and fatigue loading. Based on the strong correlation with the fatigue resistance, this study showed that the fracture toughness can be used as parameter estimating the durability of restoration in high-load-bearing areas. As a result, the selection of the restorative material should be based on its fracture toughness value. In other words, SFC should be utilized in high-stress-bearing areas to yield enhanced toughness, which make the restorations more resistant to fracture.
Methods: Ten specimens/group were fabricated either from SFC (everX Posterior, GC) or particulate filler composite (PFC;G-ænialAnterior, GC). Investigated properties were flexural strength (FS), compression strength (CS), diametral-tensile strength (DTS) and single-edge-notched-bend fracture toughness (FT) following ISO standards. Fracture resistance was determined by static load (n=10/group) and the CFL at 10 000 cycles was determined using a staircase approach (n=20/group), both on anterior composite crowns. All results were statistically analysed with analysis of variance (ANOVA) followed by Turkey post hoc test and Pearson-correlation analysis.
Results: ANOVA revealed that restorations made from SFC had higher fracture resistance (954±121N) and CFL (267±23N) (p<0.05) than the PFC. SFC revealed also higher FT (2.60 MPa·m1/2) than the PFC (1.0 MPa·m1/2). From the mechanical tests investigated, strong correlation was observed only between the FT and the CFL (r2=0.899; p <0.05).
Conclusions: Restorations made from SFC revealed promising performance under high static and fatigue loading. Based on the strong correlation with the fatigue resistance, this study showed that the fracture toughness can be used as parameter estimating the durability of restoration in high-load-bearing areas. As a result, the selection of the restorative material should be based on its fracture toughness value. In other words, SFC should be utilized in high-stress-bearing areas to yield enhanced toughness, which make the restorations more resistant to fracture.