A dicing device dices tissue harvested from a patient. The dicing device comprises a grid cutting element and a tray to receive diced tissue. The dicing device may be integrated into an otherwise conventional biopsy device. The diced tissue specimens may be further processed, such as by being introduced into a self-expanding fistula plug creation and delivery system. The self-expanding fistula plug creation and delivery system comprises a sheet and a reinforcement tube. A scaffold material may be placed in the sheet, which may then be folded and reinforced, with the scaffold material being compressed in the sheet. The scaffold material may then be pushed into a catheter end. The catheter end may be inserted in a fistula. The scaffold material may then be flushed with a cell matrix that is based on the diced tissue to create a fistula plug, which may be left in the fistula.