Bisphosphonate-associated osteonecrosis of the jaw (often abbreviated as BON, BONJ, or BON of the jaw), also called bisphosphonate-related osteonecrosis of the jaw (BRONJ) (pronounced /brɒndʒ/) or bisphosphonate-induced osteonecrosis of the jaw (BIONJ), is osteonecrosis of the jaw in a person with a history of bisphosphonate use who undergoes subsequent dental surgery.