A surgical instrument for supplying energy to tissue can comprise a jaw member comprising an electrode, wherein the electrode is configured to generate heat when electrical energy is supplied to the electrode, and wherein the electrode comprises a top surface. The surgical instrument can further comprise an insulator positioned adjacent to the electrode, wherein the insulator comprises a top surface movable between a first position and a second position relative to the top surface of the electrode, and wherein the top surface of the insulator is closer to the top surface of the electrode when the insulator is in the first position than when the insulator is in the second position.