Author/Authors :
Sharafeddin ، F نويسنده Dept. of Operative Dentistry, Biomaterials Research Center, School of Dentistry, Shiraz University of Medial Sciences, Shiraz, Iran , , Alavi، AA نويسنده Biomaterial Research Center, Dept. of Operative Dentistry, School of Dentistry, Shiraz Uni-versity of Medical Sciences, Shiraz, Iran , , Talei ، Z نويسنده Dept. of Operative Dentistry, School of Dentistry, Shiraz University of Medial Sciences, Shiraz, Iran ,
Abstract :
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 (25×2×2 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 ?exural 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 ?ber and composite type was shown to have a signi?cant positive influence on the ?exural properties of the ?ber-reinforced composite. Glass fiber has a significant influence on the flexural properties of directly- made specimens.
