Résumé
Statement of Problem: The flexure of the fiber- reinforced composites [FRC] which can be generally used instead of fixed metal- framework prostheses have been more advocated due to the enormous demands for the conservative and esthetic restoration. The flexure of the fiber should be well-fitted to its covering composite. No study has been reported the comparison of the combination of glass and polyethylene fiber with particulate filled composite and fiber reinforced composite yet
Purpose: This study compared the flexural strength of two types of fibers combined with three types of composites
Materials and Method: Sixty-six specimens were prepared in a split mold [25x2x2 mm]. The specimens were divided into six groups according to the type of resin and the fiber [N = 11]: group 1: Z250 composite + Polyethylene fiber; group 2: Build It composite + Polyethylene fiber; group 3: Nulite F composite+ Polyethylene fiber; group 4: glass fiber + Z250 composite; group 5: glass fiber + Build-It composite and group 6: glass fiber + Nulite F. The mean flexural strengths [MPa] values were determined in a 3-point bending test at a crosshead speed of 1 mm/min by a universal testing machine [Zwick/Roell Z020, Germany]. The results were statistically analyzed, using one and two- way ANOVA and LSD post-hoc tests [p< 0.05]
Results: The highest flexural strength was registered for glass fiber in combination with Z250 composite [500 MPa] and the lowest for polyethylene fiber in combination with Build-It composite [188 MPa]. One-way ANOVA test revealed that there was no statistically significant difference between polyethylene fiber combinations [p= 0.62] but there was a significant difference between glass fiber combinations [p= 0.0001]. Two way ANOVA revealed that the fiber type had a significant effect on flexural strength [p= 0.0001]
Conclusion: The choice of fiber and composite type was shown to have a significant positive influence on the flexural properties of the fiber-reinforced composite. Glass fiber has a significant influence on the flexural properties of directly- made specimens