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Continuous-Fiber Preform Reinforcement of Dental Resin Composite Restorations



H H. Xu, Gary E. Schumacher, F Eichmiller, R C. Peterson, Joseph M. Antonucci, H J. Mueller


Objectives. Direct-filling resin composites are used in relatively small restorations and are not recommended for large restorations with severe occlusal stresses. The aim of this study was to reinforce composites with fiber preforms, and to investigate the effects of layer thickness and configurations on composite properties. It was hypothesized that fiber preforms would significantly increase the composite's flexural strength, work-of-fracture (toughness) and elastic modulus.Methods. Glass fibers were silanized, impregnated with a resin, cured, and cut to form inserts for tooth cavity restorations. Also fabricated were three groups of specimens of 2 mm x 2 mm x 25 mm: a fiber preform rod in the center of a hybrid composite; a thin fiber layer on the tensile side of the specimens; and a thin fiber layer sandwiched in between layers of a hybrid composite. These specimens were tested in 3-point flexure to measure strength, work-of-fracture and modulus. Optical and scanning electron microscopy were used to examine the restorations and the fiber distributions.Results. Microscopic examinations of insert-filled tooth cavities showed that the fibers were relatively uniform in distribution within the preform, and the inserts appeared to be well bonded with the surrounding hybrid composite. Specimens consisting of a fiber preform rod in the center of a hybrid composite had a flexural strength (mean sd; n = 6) of (313 19) MPa, significantly higher than (120 16) MPa of the hybrid composite without fibers (Tukey's at family confidence of 0.95). The work-of-fracture was increased by nearly 7 times, and the modulus was doubled, due to fiber preform reinforcement. Similar improvements were obtained for the other two groups of specimens.Significance. Substantial improvements in flexural strength, toughness and stiffness were achieved for dental resin composites reinforced with fiber preforms. The method of embedding a fiber preform insert imparts superior reinforcement to restorations and may improve the performance of direct-filling resin composites in large restorations with high occlusal-loads.
Dental Materials Congress


dental restorations, fiber, insert, perform, resin composite, strength, toughness


Xu, H. , Schumacher, G. , Eichmiller, F. , Peterson, R. , Antonucci, J. and Mueller, H. (2003), Continuous-Fiber Preform Reinforcement of Dental Resin Composite Restorations, Dental Materials Congress, [online], (Accessed March 1, 2024)
Created December 31, 2002, Updated October 12, 2021