Effect of contact load upon attrition-corrosion wear behavior of bio-composite materials: In vitro off-axis sliding contact-chewing simulation

Background: In recent years, the use of composite materials as biomaterials has been increasing in dentistry. It is important to perform in vitro experiments of biomaterials before living tissue. Aim: The purpose of this work was to examine the effect of contact load upon attrition-corrosion wear behavior of bio-composite materials: in vitro off-axis sliding contact chewing simulation. Material and Method: In this study, 2 mm × 12 mm (weight × diameter) cylindrical test specimens were prepared from Filtek Supreme and Clearfil AP-X bio-composite materials with different filler structure. The surface roughness and Vicker's Hardness values of the bio-composites were measured before the wear test procedures. Then, the test specimens were subjected to off-sliding abrasion test procedures under different mechanical loads in artificial saliva and citric acid medium. Wear volume loss of bio-composite materials was determined after wear test procedures using the three-dimensional noncontact profilometer. Results: As the mechanical loading increased, the loss of wear volume in both composite materials increased irrespective of test medium. However, this increase in wear volume loss in test specimens was more pronounced in the citric acid environment. Conclusion: As a result of, the organic matrix structure (such as Ba glass particle) of the composite material contributes to more volume loss in corrosive environment.