Er,CR:YSGG lasers induce fewer dysplastic-like epithelial artefacts than CO2 lasers: an in vivo experimental study on oral mucosa.

Our aim was to assess wounds made by lasers (CO(2) and Er,Cr:YSGG) for their epithelial architectural changes and width of damage. We allocated 60 Sprague-Dawley(®) rats into groups: glossectomy by CO(2) laser at 3 different wattages (n=10 in each); glossectomy by Er,Cr:YSGG laser at two different emissions (n=10 in each), and a control group (n=10). Histological examination assessed both prevalence and site of thermal artefacts for each group. Both lasers (CO(2) and Er,Cr:YSGG) caused the same type of cytological artefacts. The 3W Er,Cr:YSGG laser produced the fewest cytological artefacts/specimen, and was significantly different from the other experimental groups: 3W CO(2) laser (95% CI=0.8 to 1.0); the 6W CO(2) laser (95% CI=0.1 to 2.0) and the 10W CO(2) laser (95% CI=1.1 to 3.0). CO(2) lasers (3-10W) generate epithelial damage that can simulate dysplastic changes with cytological atypia that affects mainly the basal and suprabasal layers. Irradiation with Er,CR:YSGG laser (2-4W) produces significantly fewer cellular artefacts and less epithelial damage, which may be potentially useful for biopsy of oral mucosa.