Tensile bond strengths of three chemical and one electrolytic etching systems for a base metal alloy.

This study compared the tensile bond strength of Rexillium III disks etched by three chemical etching systems and the electrochemical etching technique. Cast Rexillium III disks were etched by the following etching systems: electrochemical, Assure-Etch, Met-Etch gel, and Etch-It gel. Thermocycled samples were loaded to failure in tension on an Instron testing machine using a crosshead speed of 5 mm/minute. Samples etched electrochemically yielded significantly greater bond strengths than those etched chemically (p less than 0.05). The rank of the groups was: Electrochemical greater than Assure-Etch = Met-Etch greater than Etch-It. Scanning electron micrograph evaluations of the etching patterns supported the bond strength determinations.