Feldspar Ceramic Strength and The Reinforcing Effect by Adhesive Cementation Under Accelerated Aging

Abstract

This study evaluated the effect of the accelerated artificial aging (AAA) on feldspar ceramic strength and the reinforcing effect promoted by adhesive cementation with resin luting agent. One hundred twenty feldspar ceramic disks were obtained. Sixty disks were acid-etched, silanized, and coated with an experimental resin luting agent simulating the adhesive luting procedures. Four groups were created (n=30): uncoated ceramic (control group), uncoated ceramic submitted to AAA, ceramic coated with resin luting agent, and coated ceramic submitted to AAA. Biaxial flexural testing with ball-on-ring setup was carried out. Biaxial flexural strength (s_bf , MPa), characteristic strength (s₀ , MPa), and Weibull modulus (m) were calculated for axial positions z=0 (ceramic surface) and z=−t₂ (luting agent surface). Data of s_bf at positions z=0 and z=-t₂ were separately submitted to statistical analyses (a=0.05). The uncoated ceramic submitted to AAA had no significant difference in s_bf and s₀ compared with the control group. Resin coating of the ceramic increased s_bf and s₀ at z=0. The AAA increased the s_bf and s₀ for the resin-coated ceramic specimens at z=0 and also the s₀ at axial position z=-t₂. The structural reliability at z=0 and z=-t₂ was not influenced by the variables tested. In conclusion, resin coating improved the mechanical strength of the feldspar ceramic. The AAA procedure was not effective in aging the uncoated or resin-coated feldspar ceramic specimens.

Key Words:
ceramic; resin luting agent; mechanical strength; Weibull analysis.