An engine piston assembly includes a piston with two opposing boss bores, a first interlocking piston button with at least one interlocking protrusion compatible with at least one interlocking recess in the first boss bore, and a second interlocking piston button with at least one interlocking protrusion compatible with at least one interlocking recess in the second boss bore. The interlocking protrusions serve to prevent the buttons from rotating inside the boss bores and deforming an oil control ring inside an oil control ring groove of the piston assembly.