No abstract

Background : The majority of the patients treated in dentistry and oral-maxillofacial surgery departments use anticoagulant agents. These patients used to take aspirin, heparin or warfarin-derived drugs. As an alternative to these drugs, new generation oral anticoagulant agents called dabigatran, apixaban, edoxaban and rivaroxaban which have rapid effect and short half-life have been produced. Rivaroxaban is a direct factor Xa inhibitor and is frequently prescribed to patients with cardiovascular disease.Aim/Hypothesis : Bone healing plays a crucial role in success of oral-maxillofacial surgery operations. The aim of this study is to determine positive and negative effects in bone healing due to the use of rivaroxaban which is one of the new generation oral anticoagulant agents.Material and Methods : Adult male Wistar Albino rats ( N = 6), weighing between 250 and 300 g were selected. Rats were divided into two groups as control group and experiment group which is orally rivaroxaban administered. 3 mg rivaroxaban per kg body weight per day was administered to the rats by oral gavage method. In both groups, the longitudinal flap was lifted on the scalp and symmetrically two 5-mm diameter critical size defects were created on the parietal bone in the cranium. 12 bone defects were rinsed with saline and left empty then the flaps were sutured. All rats were sacrificed with overdose anesthesia at postoperative 4th week. The effect of rivaroxaban on bone healing was evaluated by histopathological analysis and new bone formation. Materials and technical feasibility used in this study were provided by

This experimental study investigates the prophylactic effect of deferoxamine (DFO) on medication-related osteonecrosis of the jaw (MRONJ). Thirty-six female Sprague Dawley rats received zoledronic acid (ZA) for eight weeks to create an osteonecrosis model. DFO was locally applied into the extraction sockets with gelatin sponge (GS) carriers to prevent MRONJ. The specimens were histopathologically and histomorphometrically evaluated. Hypoxia-inducible factor 1-alpha (HIF-1α) protein levels in the extraction sockets were quantified. New bone formation rate differed significantly between groups (p = 0.005). Newly formed bone ratios in the extraction sockets did not differ significantly between the control group and the GS (p = 1), GS/DFO (p = 0.749), ZA (p = 0.105), ZA-GS (p = 0.474), and ZA-GS/DFO (p = 1) groups. While newly formed bone rates were higher in the ZA-GS and ZA-GS/DFO groups than in the ZA group, the differences were not significant. HIF-1α levels differed significantly between groups (p < 0.001) and were significantly higher in the DFO and ZA-GS/DFO groups than in the control group (p = 0.001 and p = 0.004, respectively). While HIF-1α levels were higher in the ZA-GS/DFO group than in the ZA group, the difference was not significant. While HIF-1α protein levels and new bone formation rate were elevated in the DFO-treated group, the effect was not significant. Further large-scale studies are needed to understand DFO’s preventative effects on MRONJ and the role of HIF-1α in MRONJ pathogenesis.

In this experimental study, the prophylactic effect of systemically administered erythropoietin (EPO) in medication-related osteonecrosis of the jaw (MRONJ) was evaluated. The osteonecrosis model was established using 36 Sprague Dawley rats. EPO was systemically applied before and/or after tooth extraction. Groups were formed based on the application time. All samples were evaluated histologically, histomorphometrically, and immunohistochemically. A statistically significant difference in new bone formation was observed between the groups (p < 0.001). When new bone-formation rates were compared, no significant differences were observed between the control group and the EPO, ZA+PostEPO, and ZA+Pre-PostEPO groups (p = 1, 0.402, and 1, respectively); however, this rate was significantly lower in the ZA+PreEPO group (p = 0.021). No significant differences in new bone formation were observed between the ZA+PostEPO and ZA+PreEPO groups (p = 1); however, this rate was significantly higher in the ZA+Pre-PostEPO group (p = 0.009). The ZA+Pre-PostEPO group demonstrated significantly higher intensity level in VEGF protein expression than the other groups (p < 0.001). Administering EPO two weeks pre-extraction and continuing EPO treatment for three weeks post-extraction in ZA-treated rats optimized the inflammatory reaction, increased angiogenesis by inducing VEGF, and positively affected bone healing. Further studies are needed to determine the exact durations and doses.