Assessment of Parathyroid Hormone Serum Level as a Predictor for Bone Condition Around Dental Implants

Purpose: The aim of this prospective study was to evaluate parathyroid hormone serum level as a potential single factor of bone metabolism around dental implants. Materials and Methods: Parathyroid hormone levels were measured before implantation. Intraoral digital radiographs were taken in standardized conditions in all cases: immediately after implantation, immediately after functional loading, and 3, 6, 9, 12, 18, and 24 months after functional loading. The next phase was to align all radiographs geometrically. Two regions of interest were marked in the bone image: one in the implant neck region and another in the periapical region. Next, the entropy of the microarchitecture of the bone image was calculated, and an analysis of simple regression was performed. Results: The prospective study included 107 patients of both sexes in the age range of 17 to 67 years (mean ± SD: 45.53 ± 12.1 years). A significant relationship was observed between higher levels of parathyroid hormone (but still in the normal range) and the decrease of textural entropy in the alveolar ridge bone at 3, 6, 12, and 18 months after functional loading. However, in the periods immediately after implantation, immediately after functional loading, and 9 and 24 months after functional loading, the relationship was not statistically significant. Conclusion: Assessment of the parathyroid hormone serum level can be considered a useful method to predict bone condition around a dental implant, but not as a single factor. Keywords: dental implants, entropy, parathyroid hormone