Rapid Communication: The Effect of Low-Power He-Ne and He-Cd Laser Therapy on Wound Healing of Rats

A study of the wound healing effect on Sprague–Dawley rats using low-power He-Ne (632 nm) and He-Cd (442 nm) lasers was undertaken. Our results revealed that the percent of wound healing acceleration for animals who had wound sizes of 1.26 cm² and were treated 3 times per week with doses 1, 4, 7, and 11 J/cm² of laser irradiation were 6.98, 9.26, 14.79, and 19.47% in the He-Ne laser group, and 5.32, 7.68, 10.05, and 11.63% in the He-Cd laser group. The average number of days required to achieve 80% wound healing was 11.08 ± 0.72, 11.53 ± 0.34, and 12.68 ± 0.15 in the He-Ne laser group, He-Cd laser group, and control group, respectively. Statistical analysis (Student's t test) indicated a significant difference between each treatment group and control group (p < 0.05). A comparison of the He-Ne and He-Cd laser therapy in this study revealed from 1.57 and 7.84% difference of wound healing acceleration. The acceleration was dependent on the laser dose used. The He-Ne laser yielded better healing possibly due to higher tissue penetration.