ABSTRACT
The author had reported that laser irradiation with energy density 4J/cm<sup>2</sup> at every other days was most effective for wound healing.<br>But there is a report which described that laser irradiation with energy density under 4J/cm<sup>2</sup> was effective for wound healing too.<br>Then, the effect of irradiation with under 4J/cm<sup>2</sup> He-Ne laser on wound healing was studied. Twenty-four wister rats were subjected to this experiment.<br>A open wound, 20mm in diameter as deep as muscle layer were made on the back of anesthetized animals.<br>To find the suitable energy density of laser irradiation, the wound was irradiated with He-Ne laser by energy density of 4J/cm<sup>2</sup>, 2J/cm<sup>2</sup> and 1J/cm2 every other day until the wound completely healed.<br>The wound healing was much more accelerated by irradiation with energy density of 4J/cm<sup>2</sup> than the other group.<br>This result suggested that laser irradiation with energy density 4J/cm<sup>2</sup> at every other days is most effective for wound healing.