"Torn edges" refers to the rough, jagged or uneven ends or sides of a piece of paper, fabric, or any material that has been ripped or torn apart. Full definition
Several of the paintings are executed on shaped paper which have been crafted with roughly torn edges. (michaelrosenfeldart.com)
He would often trace the ragged cut or torn edges of paper with his brush, and he frequently adjusted his colors to match adjacent swaths of paper. (milesmcenery.com)