Abstract:
Lasers of di erent wavelengths are being used in oral surgery for making incisions and excisions with minimal bleeding and pain. Thulium bre laser, with its 1940 nm emission, is well absorbed by water, making it a promising tool for oral soft tissue surgery. This study was conducted to investigate the potential of Tm: bre laser as an incisional and excisional oral surgical tool. Both 1940 nm Tm: bre and 980 nm diode laser were used on ovine tongues in this study for comparative purposes. Both lasers were applied in contact to the tissue, which was completely submerged in saline solution, via a 600 mm bre. The incisions were made by moving the bre tip manually at di erent speeds (0.5, 0.75 and 1 mm/s) and with making single, three or ve passes, using three di erent power settings (2.5,3 and 3.5W for Tm: bre and 12,14 and 16W for diode laser). The samples were stained with H&E for microscopic evaluation of depth of ablation and extent of coagulation, and ablation e ciencies were calculated. Deeper ablations, as well as larger coagulations were obtained with both lasers by using higher power settings. However, making more passes at constant power yielded deeper ablations without signi cantly larger coagulation zones. Furthermore, increasing the speed caused shallower ablation and narrowed coagulation zones. Microscopically, a narrow vacuolization and a large coagulation zone were observed for 1940 nm Tm: bre laser, whereas the coagulation zone produced by 980 nm diode laser was larger and no vacuolization was evident.|Keywords : Laser surgery, fibre laser, oral surgery, thulium.