Table 4. Means and standard deviations (±) for E (GPa) values of the enamel comparing type of irradiation, pH-cycling and enamel depths.
| Irradiation | Enamel depth | No pH cycling | pH cycling | ||
|---|---|---|---|---|---|
| Mean (±) | Pooled Average | Mean (±) | Pooled Average | ||
| Non-irradiated | Superficial enamel | 45.5±3.5 | 44.3±3.3Bc | 59.5±1.4 | 61.3±2.9Ab |
| Middle enamel | 45.1±3.3 | 61.5±5.0 | |||
| Deep enamel | 42.4±3.1 | 63.0±2.4 | |||
| Irradiated | Superficial enamel | 70.4±3.8 | 68.6±2.3Aa | 73.2±7.4 | 69.9±7.1Aa |
| Middle enamel | 68.5±2.2 | 69.1±7.8 | |||
| Deep enamel | 66.9±0.9 | 67.5±6.1 | |||
| Irradiated in fluoride | Superficial enamel | 62.9±3.7 | 61.6±2.9Bb | 75.2±11.9 | 74.1±11.3Aa |
| Middle enamel | 61.2±4.0 | 73.9±12.4 | |||
| Deep enamel | 60.8±4.4 | 73.1±9.6 | |||
*
Different uppercase letters show significant differences between pH cycling. Different lowercase letters show significant differences for irradiation factor