Impact of Osteoporosis on Autogenous Bone Graft Resorption

Background Osteoporosis is a common disorder that is characterized by decreased bone density and increased bone resorption. This bone resorption may affect the grafted bone during the maxillofacial reconstruction. Purpose This study aimed to measure the association between osteoporosis and resorption of anterior iliac crest bone grafts (AICBGs) used to reconstruct the atrophic anterior maxillae. Study design, setting, and sample This prospective cohort study included female patients requiring bone augmentation of the anterior maxilla. Patients with a ridge width of < 4 mm and ridge height of > 7 mm were enrolled in the study. Exclusion criteria were chronic use of corticosteroids or intravenous bisphosphonates, history of maxillofacial radiation therapy, current smoking, and underlying conditions contributing to bone metabolism (e.g., hyperparathyroidism, chronic renal failure, and hypophosphatemia). Predictor/exposure/independent variable Osteoporosis status was a predictor variable. Patients were allocated to the osteoporosis or control group based on T-scores obtained by dual-energy X-ray absorptiometry (DEXA). Mean T-scores ≤ -2.5 were assigned to the osteoporosis group. Main outcome variable(s) The outcome variable was graft resorption, defined as the difference in ridge width between measurements made immediately (T1) and six months postoperatively (T2) using cone-beam computed tomography (CBCT). Covariates Patient age, pre-operative (T0) bone width, and the amount of bone augmentation, defined as the differences in ridge width between measurements made preoperatively (T0) and immediately after grafting (T1), were covariates of this study. Results Thirty-two patients were included in the study (15 in the osteoporosis group and 17 in the control group). The amount of graft resorption at six-months after grafting was 2.57 ±0.59 mm in the osteoporosis group and 0.97±0.59 mm in the control group (p<0.001). A significant correlation was found between the mean T-score and graft resorption six months after grafting (p<0.001). Conclusion A significant correlation was observed between osteoporosis and graft resorption in the anterior maxilla after six months.