Subclinical Necrotic-Bodies Detected by CBCT in IV Bisphosphonate-treated Cancer patients

Objectives: Osteonecrosis of the jaw (ONJ) is characterized by exposed necrotic bone that does not heal after 8 weeks in the absence of radiation to the head and neck in patients receiving intravenous bisphosphonate (BP) treatment. ONJ lesions are difficult to manage and an early diagnosis would be beneficial for preventing their development. Cone-beam Computerized tomography (CBCT) is a high resolution scanner that produces 3D images of mineralized tissues. Reconstructed images can be viewed in sagittal sections giving high resolution images of alveolar bone. We hypothesized that following exposure to BP, alveolar bone will contain subclinical lesions that may be detectable by CBCT before presenting as a visible sequestrae of dead bone. In the present study CBCT scans of subjects receiving BP treatment were analyzed and compared to subjects not receiving BP treatment. Methods: Subjects diagnosed with ONJ were scanned using CBCT. Scans were reconstructed, oriented by a specific landmark (single-rooted tooth) and analyzed for the presence of necrotic-bodies. Results: CBCT scans revealed the presence of necrotic-bodies within the mandible and/or maxilla of ONJ patients. Necrotic-bodies were observed that resemble small “islands” of bone, surrounded by resorbed areas. 33 normal subjects and 33 ONJ patients were analyzed and necrotic-bodies were observed in 19 of the 33 subjects previously diagnosed with ONJ. No necrotic-bodies were observed in non BP-treated subjects Conclusion: Non-clinically visible ONJ lesions as detected by CBCT appear with high incidence in cancer patients, even in edentulous patients. CBCT is an imaging modality that may prove useful in the regular dental practice to identify patients who are at risk for developing ONJ. Baseline and longitudinal imaging will aid in understanding the progression of the pathological changes in bone in these patients and will help oncologists and dentists as they collaborate to provide the best patient care possible.