Effect of Morphine Dependency on Bone Repair Process in the Cortical Bone of Tibia in Rats

Several environmental factors have been found to affect the process of bone healing including malnutrition and smoking. to our knowledge, the effect of addiction on bone repair process has not been studied yet. this study was designed to investigate the effects of morphine dependency on bone repair process in rats. fifty six rats were divided into two groups randomly, each group containing 28 rats. the rats in study group got morphine by adding morphine powder to their water for 21 days. then morphine dependency was confirmed by injecting naloxon intra-peritoneally. both groups underwent surgery and a fixed round hole was created in anteromedial aspect of the tibia. bone biopsy was performed on days 3, 6, 10 and 20, on 7 randomly selected rats from each group and the results of microscopic study were analyzed by mann whitney test. there was statistically significant difference between the two groups according to neutrophilie exudates percentage and granulation tissue formation on 3rd day (p < 0.005), neutrophilie exudates percentage (p = 0.01) and immature bone formation on 6th day (p < 0.005), immature bone formation (p = 0.001) and mature bone formation (p < 0.05) on 10n day and mesenchymal tissue formation on 20th day (p < 0.05). it is concluded that the process of bone repair in a hole created in the rat tibia is markedly delayed in morphine-dependent rats