Effects of low‐level energy lasers on the healing of full‐thickness skin defects

Effects of low‐level helium‐neon laser radiation were compared on (1) wounds that closed primarily by contraction and (2) the breaking strength of straight‐line incisions. Circular full‐thickness skin defects in rabbits received dosages of 1.1 J/cm² during a 30‐min exposure every third day, and 2.2 J/cm² during a 3‐min exposure twice daily until wound closure. No significant differences in healing were observed between laser‐treated wounds and untreated control wounds. Conversely, rat skin incisions exposed to 2.2 J/cm² for 3 min twice daily for 14 days demonstrated a 55% increase in breaking strength over control rats (p <0.01); 28 days postoperatively, this difference in breaking strength diminished to a nonsignificant 16% increase over the control rats. Increasing the dosage to 4.5 J/cm²yielded a nonsignificant 17% increase over the control rats 14 days postoperatively. HeNe laser irradiation of wounds increases certain aspects of healing in the early stages, but not to such a degree as to be clinically applicable. More detailed research is indicated to obtain optimal exposure levels necessary to accelerate wound healing significantly.