Abstract

The present study was designed to Study the effect of low level laser therapy of continuous diode laser at 810 ± 10 nm on repair Tibia chronic defect in rabbits. Eight adult rabbits were employed to induce 3 mm in diameter chronic defect in Tibia, by insert the stainless steel screw in the induced hole for one and half month post operation, then the stainless steel device removed to create the chronic bone defect. The animals were divided to two equal group, the control group of 4 rabbits were followed up for normal healing processing without any treatment, while the treatment group was exposed daily to single dose of continuous diode laser at 810 ± 10 nm, 500 Ma for 10 minutes at 72 hours
interval for 14th days at the medial aspect of the Tibia. The results of the clinical observation were same in both groups which revealed body depression with loss appetite, immediately after surgical operation, which retained to normal after few days, and the inflammatory signs at the surgical wound, disappear with satisfactory wound healing after 5 to 7 days post operation, the radiographic finding at the end of the first and second week post irradiation in the treatment group shows increase sclerotic area around the chronic defect margin more dense and wide with
decrease in the bone defect diameter compare with the control group, while the macroscopic examination at the end of the experimental period were same in both group which show heavy fibrous connective tissues fill the chronic defect, while the microscopic examination revealed profuse and more prominent osteoblast cells blood vessels angiogenesis and lamellar bone formation more obvious and clear in the treatment group compare with the control group at the end of the experimental period. The conclusion is low level laser therapy by continuous diode laser at
the 810 ± 10 nm can be used for repair of induced chronic defect of Tibia in rabbits.

Keywords: Bone repair; Continuous diode laser; induced chronic defect of Tibia; Low level laser therapy