Database analysis of the risk factors of bisphosphonate-related osteonecrosis of the jaw in Hungarian patients.

Objective: Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is a rare but serious side effect of bisphosphonates (BPs). Since this disease has no independent code in either of the diseases' or in the medical procedures' classifications, it is hard to estimate how many BP patients are affected.

Design: A retrospective observational epidemiological registry-based study was carried out, using the data of the national service of Hungary on the incidence of BRONJ and related factors.