Isfahan University of Medical SciencesDental Research Journal1735-33272120080120In Vitro Study of Fracture Strength of Resin-bonded Glass Fiber-reinforced Composite Anterior Fixed Partial Dentures1919MostafaSadeghi. drj@dnt.mui.ac.irLindsayRichards20101106Background and aim Restorative dentistry searches the use of glass fiber-reinforced composite is just now experiencing rapid expansion in dentistry. This study compared of fracture strength a glass fiber-reinforced composite (GFRC) and a fiber-reinforced composite (FRC) as a framework for fabrication of resin-bonded fixed partial dentures (RBFPDs). Methods and Materials Twenty RBFPDs were made with GFRC (everStick) and FRC (Ribbond). The specimens were stored for 2 weeks at 37 1 C in distilled water, thermocycled (5-55C, x 2500) and statically loaded to fracture. The hounsfield testing machine measured fracture strength of the samples. Metal cone with tip 1 mm income vertically to central of labial surface of pontic with speed 1 mm/min. The force in Newtons was recorded at debonding of prothosis from abutment teeth and then SEM. Results The mean and standard deviation for fracture strength of GFRC RBFPDs were 440±75 and for FRC RBFPDs were 309±33. ANOVA showed that fracture strength between two groups were statistically significant (pv =0.000247). SEM examination revealed that debonding between the GFRC RBFPDs and the tooth and no debonding between the glass bundle and the composite. Conclusion On the basis of the results of this study, GFRC that can be used in the fabrication of 3-unit anterior FPDs. Key Words glass fiber-reinforcement, resin-bonded, fracture strength, composite, fixed partial dentures