highly significantp = 3.728 × 10 –11
In paired comparisons of the different materials with the identical surface treatments, all groups showed highly significant differences (groups 1 and 4 p = 3.728 × 10 –11 ; groups 2 and 5 p = 7.721 × 10 –6 ; groups 3 and 6 p = 1.725 × 10 –6 Figure 6 ). 3.2.2.