Comparative study of skin welding in the rat using low power CO₂ laser beam - Macroscopic observations, histologic and histochemical studies using Picrosirius red stain for collagen determination

In 50 rats, a full thickness abdominal skin incision was made with a C0₂ laser (LI) (Kaplan PenduLaser 115) and in another group, an incision was made by a scalpel (SI). These groups were divided into 2 subgroups: a Iow power C0₂ laser skin welding of 500 mw was used in LI and SI subgroups and, in the other, the wound was closed with nylon sutures. On the 4th postoperative day in the LI welding group, a complete dehiscence wound was formed in one animal and in the SI welding group, a partial dehiscence. After one week, a thin line of young (fresh) scar was observed with complete healing after 2 weeks. Histology revealed after 4 days, a deep cleft in the LI and SI welding groups and a superficial ulcer after one week and after 2 weeks, all groups showed complete healing. Histochemical studies (Picrosirius red stain) revealed in the first 2 weeks, greenish-yellow polarized colors and red-orange colors of a matured collagen in the well-formed scar. It appears that there was no delay in the healing process between the LI and SI groups and between welding and suture healing.