Eyespecial c 4

After the SBS test, each surface on both zirconia and metal bracket was observed under a light microscope (magnification×20, Magnifier Light, AS ONE, Osaka, Japan). The ARI was determined based on the presence of cement remaining on the zirconia, and the optimal images were recorded by a dental digital camera (EyeSpecial C-IV, Shofu, Koyoto, Japan ) (Fig. 3). The score is represented by a scale with five levels, ranging from 1 to 5: score 1 (A): almost all cement left on the zirconia surface; score 2 (B): more than 90% of the cement left on the zirconia surface; score 3 (C): more than 10% but less than 90% of the cement left on the zirconia surface; score 4 (D): less than 10% of the cement left on the zirconia surface; score 5 (E): no cement left on the zirconia surface. NS means no significant differences (p>0.05). The same capital letters indicate no significant differences in SBS for each row (p>0.05). The same number indicates no significant differences within each bracket at 24 h and thermocycling (p>0.05). To minimize deviations, all images were randomly selected and scored for ARI indices by three calibrated examiners. In case individual scores differed among the examiners, the majority score was chosen to be the final score.