Histological and Histomorphometric illustration the endochondral ossification of the mandibular angle defect repair in rats after oral stimulation with bisphosphonate treatment (an in vivo study)

Background: Bio-phosphonates can be used to lower the risk of hip and spine fractures. Additionally, they can be used to treat Paget's disease of the bones in a variety of dosages. In the procedure that replace hyaline cartilage to bone, this procedure i.e. called endochondral ossification. It starts when mesenchymal cells from the mesoderm develop into chondrocytes. Chondrocytes multiply quickly and release an extracellular matrix to create the cartilage that serves as the model for bone. Objective: To histomorphometric illustration the endochondral ossification of the mandibular angle defect repair in rats after- oral stimulation with bisphosphonate treatment. Patients and Methods: 20 rats were used in this work and the animals were divided into the following groups: 10 Rats from the control group. The bone defect was healed naturally without medicament and 10 rats were used in the experiment, and taking the biophosphonate medication helped mend the bone defect. Every single group was studied in 7 and 14 day (5 rats for each healing period) and the surgical procedure was performed for histological and Histomorphometrically examination. The data analysis with spss statistic measure & with P vale (P ≤ 0.05). Results: Active effect of the bio-phosphate medicament in the endochondral ossification and the cell that responsible for the cartilage formation and accelerated the healing of the mandibular defect with inhibition of the bone resoption and finally decrease the time that need to full healing. Conclusion: The chemical medicament that represented by bio-phosphonate accelerated the endochondral ossification in a short time and replacement with bone in the site of the defect. Keywords: Bio-phosphonates, Cartilage, Chondrocytes, endochondral ossification.