In this technical approach, we demonstrate that preoperative tetracycline administration helps distinguish between viable and necrotic bone in osteoradionecrosis (ORN) during surgery by exciting tetracycline fluorescence by black light. The difficult aspect of the operative approach lies in the decision of the extent of the debridement in order to prevent an iatrogenic fracture or progression of ORN. With this technique, vital bone, in contrast to necrotic bone, showed detectable fluorescence. Therefore, tetracycline fluorescence labeling may be used in attempts to facilitate the intraoperative decision making in the surgical therapy of osteoradionecrosis.