Abstract
The purpose of this study was to examine vickers hardness, changes in the ability of acid resistance and changes in crystallography using X-ray diffraction of enamel after Nd: YAG laser irradiation.
The following results were obtained:
1. The Vickers hardness of enamel after Nd: YAG laser irradiation at 100 mJ output increased significantly.
2. The Vickers hardness of dentin after Nd: YAG laser irradiation at 100 mJ output increased significantly just as in the enamel.
3. The results of acid resistance examined using QLF showed a statistically significant difference between the two groups. The non-laser irradiation group ofΔF(average of depth of demineralization)was-9.68±1.90, while the laser irradiation group was -7.75±1.31.
4. The SEM image showed a smooth surface structure, while numerous irregular micro cracks, large or small numerous micro holes were observed.
5. The results of X-rd diffraction Showed decomposition and created β-TCP in at some of the enamel after Nd: YAG laser irradiation.
