The objective of this study aimed to assess the effeats of the CO2 laser on the enamel cracks. The labial cracks of thirty extracted central incisors were irradiated with 4 Watts power and (0.4, 0.2 and 0.1) pulse durations. The laser used was CO2 laser with 10.6 μm in wavelength. The irradiated samples were sectioned into ground cross sections and examined under polarizing microscope. Enamel cracks can not be welded completely using CO2 laser irradiation. Although the formation of superficial

more »

... laze layer, there was a tendency to increase in the separation of the crack sides as the pulse duration of the laser increased