Effect of Different Power Parameters of Er,Cr:YSGG Laser on Dentin Ablation Ability and Substrate Morphology

The aim of this study was to assess the effect of different power irradiation conditions on human dentin by pulse Er,Cr:YSGG laser. Tissue samples were derived from freshly extracted human molars. The wavelength of pulse Er,Cr:YSGG laser was 2.78 m μ , pulse repetition rate was 20Hz and pulse duration was 140 s μ . Laser power of irradiation varied from 1.5 to 4 W. Laser energy was delivered through a fiber optic system to a handpiece containing a tip with a diameter of 600 m μ . After irradiation, the morphologic characteristics of ablation craters were measured by use of both stereomicroscope and optical coherence tomography (OCT). Then the specimens were prepared for scanning electron microscope (SEM). The results indicated that Er,Cr:YSGG laser was capable of ablating human dentin. The diameter of ablation craters increased with the output power; the crater depth and ablation volume showed a linear growth with the output power.