Fractal Dimension and Pixel Intensity in the Alveolar Bone Healing after Tooth Extractions in Individuals with Kidney Diseases

Abstract Objective: To assess and compare radiographically alveolar bone after tooth extractions in individuals undergoing renal dialysis (CKF), those submitted to kidney transplantation (KT) and those without kidney disease (CG) by using fractal dimension and pixel intensity. Materials and methods: 54 periapical radiographs of 17 control individuals, 40 periapical radiographs of 12 KT individuals and 156 periapical radiographs of 48 CKF individuals were analysed at 7 and 60 days after tooth extraction. Image J software was used to determine the alveolar bone density based on fractal dimension and pixel intensity, which expresses the structural complexity of the trabecular bone. Results: The difference in fractal dimension after tooth extractions made at 7 and 60 days was significantly smaller in KT individuals (0.03) compared to control (0.12) and CKF (0.11) ones (P < 0.05), which indicates a gain in the trabecular bone in the alveolus. In KT individuals, the serum levels of calcium showed a moderately negative correlation with fractal difference (r = - 0.517) and pixel intensity (r = - 0.589) at 60 days, including a difference in pixel intensity at 7 and 60 days (- 0.667). Conclusions: Gain in trabecular bone complexity and alveolar bone density were lower in KT individuals, thus being correlated with the serum levels of parathormone, creatinine and calcium. Clinical relevance: As prevalence of CKD increases worldwide and advancements in treatment of this disease improves life expectancy, it’s important to know how socket bone healing happens in these individuals, to future oral rehabilitation with osseointegrated implants.