Effects of vitamin D in comparison to parathyroid hormone in medication-related osteonecrosis of the jaw induced rat

Abstract

Medication-related osteonecrosis of the jaw (MRONJ) refers to a disease in which the jaw does not heal properly after an invasive procedure and becomes necrotic; its causes include anti-angiogenic drugs and anti-resorptive agents, such as bisphosphonate (BP). The objective of the present study was to assess whether efficacy of vit.D is identical to that of PTH in treating MRONJ through an animal experiment using a rat model. After inducing MRONJ by administering BP for 6 weeks prior to and 4 weeks after tooth extraction, 36 rats were divided into the control, PTH, and Vit. D groups (12 rats per group). PTH and Vit. D were administered daily for 4 weeks, after which the animals were euthanized and tissue samples were harvested from the mandible, including the extraction sockets of the mandibular first and second molars (M1 and M2, respectively), and the tibia and interseptal bone of the mandibular third molar (M3). Macroscopic, histological, and micro-computed tomography (micro-CT) examinations were performed. In the macroscopic and histological examinations, good healing was found in the PTH, Vit. D, and control groups, in that order; however, the differences were not statistically significant. In the micro-CT examination, a statistically significant difference in the bone volume fraction was found in the extraction socket and mandibular M3 region in the PTH group and only the M3 region in the Vit. D group, as compared to the control group (p<0.05). The findings of the present study showed that both PTH and Vit. D were effective in the treatment of MRONJ, with PTH showing more favorable results. Vit.D may be used as an alternative to PTH, additional studies on its dosage and duration of administration are needed.