Electron microscopy comparison of CO2 laser flash scanning and pulse technology one year after skin resurfacing

Background The recent adaptation of laser technology in plastic and dermato logic surgery has provided a means to reduce efficiently the irregularities of the surface of the skin. Previous studies have analyzed the short- and medium-term clinical and histologic results of two laser systems: the Sharp lan 400 SilkTouch(TM) and the 5000C Coherent Ultrapulse(R) with Computer Pa ttern Generator(R) (CPG). This paper contains the long-term ultrastructural findings observed with the aid of transmission electron microscopy (TEM). Materials and Methods Twenty skin biopsy specimens were taken from ten Cauc asion patients, between 54 and 72 years of age, who had undergone facial sk in resurfacing with a CO2 laser 1 year previously. The treated areas of the face were divided into two equal parts. One half of the face was treated w ith the Sharplan SilkTouch(TM) laser and the other half with the Coherent U ltrapulse(R) laser. Using TEM, the cell composition of the epidermis was st udied ultrastructurally, as were the dermal-epidermal junction (DEJ) and th e different fibers and cells in the superficial and middle dermis. Results On the side treated by the Sharplan(TM) laser, little melanin was o bserved, the DEJ was thicker, and there were abundant collagen fibers well compacted in the dermis. Also present was abundant elastin fiber with scarc e interstitial spaces. On the side treated by the Coherent(R), the melanin was abundant and the DEJ was well structured. There were fibroblasts with l ax chromatin in the dermis and collagen fibers in the papillary dermis orie nted in a vertical and horizontal manner in relation to the epidermis. Ther e was little elastin. The interstitial spaces were abundant. Conclusions The Sharplan(TM) laser system seems to provoke a significantly more intense tissue response, with abundant dermal collagen and elastic fib ers. This indicates that the Sharplan 40C SilkTouch(TM) might produce longe r lasting clinical effects.