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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Aged, Aged, 80 and over, Bone Density, Bone Density Conservation Agents, Bone Matrix, Case-Control Studies, Diphosphonates, Female, Humans, Jaw Diseases, Male, Middle Aged, Osteonecrosis, X-Ray Microtomography.
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Does higher bone matrix density exist in only a subset of patients with bisphosphonate-related osteonecrosis of the jaw? Context: Because few treatment options exist for bisphosphonate-related osteonecrosis of the jaw (BRONJ), developing methods of early detection and prevention is vital. Computed tomography could represent a useful tool for early detection of BRONJ, yet its effectiveness would necessitate changes in tissue density. The aim of this study was to quantify bone matrix density of tissue from patients with BRONJ. Bone samples from 13 patients with confirmed BRONJ were scanned by use of high-resolution micro-computed tomography. Mean density and density distribution were assessed and compared with mandible samples from cadaveric controls (n = 8; age range, 43-94 years). The bone matrix in BRONJ samples had a significantly higher mean density (+8.5%, P = .01) compared with cadaveric samples. The higher density in BRONJ tissue was evident in a clear shift in the tissue density profile. In controls, less than 5% of the tissue had a density above the median gray-scale value, whereas on average, BRONJ tissue had approximately 15% of the tissue density in this range. By use of z score analyses of mean density values, a large degree of heterogeneity is evident among BRONJ specimens, with some samples having z scores of 0 and others having z scores well above 6 compared with controls.
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On the basis of these findings, higher tissue density appears to manifest in only a subset of BRONJ patients, suggesting that density may have limitations as a biomarker for early detection of this condition. Final Decision: yes