Effects of laser therapy in CO2 laser wounds in rats

Photomed Laser Surg. 2006 Jun;24(3):389-96. doi: 10.1089/pho.2006.24.389.


Objective: The aim of this study was to assess the effects of laser therapy and its possible dose dependency on the healing of CO2 laser surgical wounds.

Background data: Several reports from our group and others have indicated that light therapies may improve healing, depending on wavelength, dose, intensity of the light, and both local and systemic conditions.

Methods: Circular surgical wounds were created on the dorsum of Wistar rats, which were separated into three groups (A, B, and C). Group A acted as control and had no additional treatment. Groups B and C were irradiated with GaAlAs lambda685-nm laser light, either with 20 J/cm2 (Group B) or 40 J/cm2 (Group C). The animals were humanely killed at the end of the experimental period; specimens were taken and routinely processed to wax and stained with Hematoxylin and Eosin, Sirius Red, and alpha-Smooth Muscle Actin (alphaSMA).

Results: Laser-irradiated groups showed a healing process characterized by a more prominent fibroblastic proliferation, with young fibroblasts actively producing collagen; no myofibroblasts were found. No statistically significant differences were observed when the different doses were compared.

Conclusion: It may be concluded that, using this methodology, laser therapy has a positive effect in wound healing produced by CO2 laser, and the dose has no influence on the treatment.

MeSH terms

  • Animals
  • Carbon Dioxide / adverse effects
  • Cell Proliferation
  • Collagen / metabolism
  • Fibroblasts / metabolism
  • Low-Level Light Therapy*
  • Male
  • Rats
  • Rats, Wistar
  • Wound Healing / radiation effects*
  • Wounds and Injuries / radiotherapy*


  • Carbon Dioxide
  • Collagen