Table 2.
Mean (standard deviation) values of bond strength (MPa) and Mann–Whitney test
| Groups | N | Mean (SD) | Median | 95% CI | |
|---|---|---|---|---|---|
| G350 | A | 12 | 27.0 (3.2)b | 28.0 | 24.94–29.06 |
| B | 12 | 32.42 (3.2)a | 32.0 | 30.35–34.49 | |
| G60 | A | 12 | 30.75 (3.5)a | 31.0 | 28.47–33.03 |
| B | 12 | 31.42 (2.8)a | 30.0 | 29.61–33.22 | |
| GBF | A | 12 | 30.33 (3.9)a,b | 29,0 | 27.82–32.85 |
| B | 12 | 28.92 (2.5)b | 27,5 | 30.35–34.49 |
Notes: Mann–Whitney test; different letters (a and b) after the median value stand for significant differences with treatment (p<0.008). Subgroup A: conditioned with phosphoric acid at 37%. Subgroup B: submitted to surface abrasion with a diamond rounded tip + conditioned with phosphoric acid at 37%.