Experimental studies on the effect of low energy CO2 laser on wound healing. The effect on the healing of full thickness skin defect.

The following experiments were performed to examine the effect of low-power density CO2 laser on wound healing process.1.The temperature alteration of normal rat dorsal dermi irradiated by CO2 laser, was measured by cromel-almel thermo-couple.2.The healing of full thickness skin defects, produced in rat's dorsums and irradiated by low-power density CO2 laser was examined by the following procedures.(1) Wound area was arithmetically measured daily.(2) Hydroxyproline content was spectrophotometrically determinedby Edward's method, and water content was determined at the same time.(3) Histological findings were obtained after staining with hematoxylin and eosin.The results were as follows.1.Rise of skin temperature was related to power density and irradiation time.2.The wound areas of irradiated groups reduced more than those of control group at 3-7 experimental days.3.At 4-14 experimental days, the hydroxyproline contents of the wounds increased more in irradiated groups than in control group.4.The wounds water content decreased and returned to normal level faster in irradiated groups than in control group.5.Histological findings of rat's dorsal dermis suggested that the wounds of irradiated groups healed swifter than those of control group, and the arrangement of collagen fibers were more well-ordered in irradiated groups than in control group.6.Low-power density CO2 laser had thermal effects, and these effects activated collagen synthesis in the early phases of wound healing.