Comperati̇ve effect of ni̇gella sati̇va wi̇th dental pulp mesenchymal stem cell therapy on heali̇ng of rat ti̇bi̇al bone defect

One of the biggest problems in jaw surgery is the repair of the bone defect. Bone tissue cannot provide fully heal over a defect of a certain size. This size is considered to be an average of 7 mm and is called the critical size bone defect. In defects over this size, bone tissue is supported by artificial bone materials and biological agents to help it heal. These biological agents have a wide variety from various vitamins to laser and ozone application. In the literature, new ones are added to these items without losing their timeliness. In this study, we aimed to determine the effectiveness of a current agent, Nigella Sativa, on bone healing together with dental pulp-derived mesenchymal stem cells. In our study, 28 Sprague Dawley male rats were used. Rats were divided into 4 groups. In the positive control group, only the defect on the tibia bone was opened with a trephine bur, and saline was applied and then closed. In the second group, the defect was opened with a trephine bur on the tibia bone, then closed and Nigella sativa was applied by gavage. In the 3rd group, the defect was opened with a trephine bur, then closed and stem cells was given locally. In the 4th group, the defect was opened with a trephine bur. After the defect was closed, Nigella sativa was given to the rats by gavage and stem cells was applied locally to the defect area. All animals was sacrificed at the end of the 4th week and the removed tissues was subjected to histomorphological examination in fixative solution. As a result of our study, it was observed that only thymoquinone or stem cell therapy partially stimulated bone growth and supported the development of new bone trabeculae after defect creation. After the defect was created, it was observed that stem cell + thymoquinone treatment was much more effective than only thymoquinone or only stem cell treatment, inducing more bone trabeculae development, contributing to matrix and connective tissue formation, and increasing the number of osteoblasts and osteocytes involved in bone formation. Based on these results, it was concluded that the combined application of stem cells and nigella sativa is important in terms of healing in defects. However, further research is needed to better understand these features.