Reinforcement of denture base resin with short vegetable fiber

Abstract

ObjectivesShort ramie fibers were selected to investigate the effect of fiber length and volume fraction on the flexural properties of ramie fiber reinforced denture base PMMA. With the aid of measured interfacial shear strength and theoretical prediction values, experimental results were well interpreted. MethodsInterfacial properties between denture base PMMA and ramie fibers were evaluated by single fiber pull-out test. Then, chopped ramie fibers were pre-stirred with PMMA powder by a mechanical blender and then mixed with MMA liquid to fabricate composites. Two crucial influencing factors, fiber volume fraction and fiber length, were studied to clarify their effects on flexural properties of composites. ResultsWith 1.5mm fibers addition, flexural modulus of denture base PMMA rose from 2.50 to 3.46GPa with 10vol.% fibers, while flexural strength declined steadily with increment of fiber content. If fiber length was 3.0mm, the modulus showed a growth to 3.5GPa at 4vol.% fiber content followed by a drop to 3.00GPa at 10vol.%, whereas fluctuation in strength was experienced. Experimental results were discussed by comparison with two theoretical models. SignificanceShort ramie fiber reinforced denture base PMMA had higher flexural modulus than neat resin, while strength was lowered due to the weak interfacial adhesion. The potential of vegetable fibers as reinforcing agents for denture base should be further investigated by strengthening the interface between cellulose and denture base PMMA.