This study analyses the skin contracture effect of the erbium:YAG (Er:YAG) laser on the skin of rats by light microscopic histological and morphometrical evaluations. Two squares of back skin were precision tattooed on each of the animals (n = 35), that were termed control and experimental skin. The experimental skin was treated with three passes of the Er:YAG laser with standardized parameters. Five animals were killed and skin specimens were analyzed at 00, 07, 14, 28, 56, 84 and 112 days. Histologic examination demonstrated a mean of 215.24 micrometers ablative damage that was homogeneous with complete vaporization of the epidermis and superficial dermis. The residual thermal damage was small (mean of 41.45 micrometers) observing areas where it was absent. The cicatritial fibroplasy was present at day 07 (mean 55.58 micrometers) rising quickly until day 28 (mean of 209.49 micrometers) when it reaches a plateau and maintaining it until day 112. There are no signs of acute inflammatory process at day 07 and the reepithealization was complete at this day. This study revealed that the laser had induced shortening of the treated areas which persisted beyond the 112 days.
Erbium; Rats; Fibroplasy
