The labeling index (ratio of TGFβ1 expressing cells/total number of fibrous tissue-related cells) was significantly diminished (p < 0.032) in the BRONJ group and significantly increased (p < 0.04) in the osteoradionecrosis group compared to the control mucoperiosteal tissue (Table 1; Figure 2d). The gene discussed is TGFB1; the disease is osteoradionecrosis.