Group | Subgroup | N | Description |
---|---|---|---|
Control group | – | 20 | No further treatment of dentin slices |
Etchant group | – | 20 | Dentin slices were etched with 350 g/L phosphoric acid (Gluma, USA) for 20 s and washed thoroughly with plenty of water for 20 s to avoid excessive drying and to maintain wettability |
Energy groups (Er:YAG laser treatment; variable energy; frequency of 10Â Hz) | 50Â mJ group | 10 | Dentin slices were irradiated using an Er:YAG laser (Fotona, Slovenia) with the R14 handle. The laser was adjusted to the multi-streaming processor (MSP) mode and the optical fiber (diameter 0.6Â mm) was applied vertical to the surface of the sample for about 1Â mm, followed by irradiation using the mesh scanning mode for 10Â s at a frequency of 10Â Hz and wavelength of 2940Â nm, with 60% water, 40% steam, and variable energy (50Â mJ, 100Â mJ, 150Â mJ, 200Â mJ, 250Â mJ, and 300Â mJ) |
100Â mJ group | 10 | ||
150Â mJ group | 10 | ||
200Â mJ group | 10 | ||
250Â mJ group | 10 | ||
300Â mJ group | 10 | ||
Frequency groups (Er:YAG laser treatment; variable frequency; energy of 100Â mJ) | 5Â Hz group | 10 | Dentin slices were irradiated using the Er:YAG laser with the R14 handle. The laser was adjusted to MSP mode and the optical fiber (diameter 0.6Â mm) was applied vertical to the surface of the sample for about 1Â mm, followed by irradiation using the mesh scanning mode for 10Â s at an energy of 100Â mJ and wavelength of 2940Â nm, with 60% water, 40% steam, and variable frequencies (5Â Hz, 10Â Hz, 15Â Hz, 20Â Hz, 25Â Hz, and 30Â Hz) |
10Â Hz group | 10 | ||
15Â Hz group | 10 | ||
20Â Hz group | 10 | ||
25Â Hz group | 10 | ||
30Â Hz group | 10 |