Effect of surface treatments on the surface morphology of zirconia ceramic

Abstract

Objective To investigate the surface morphological changes of zirconia ceramic after different surface treatments.Methods Forty-eight square specimens of sintered zirconia ceramic,6 mm×6 mm×2 mm in volume,were allocated to 4 groups(n=12 each) by random digits table which were respectively subjected to no surface treatment (group A),airborne-particle abrasion with 120 μm A12O3 particles (group B),selective infiltration etching (SIE) with IPS e-max ceram glaze paste as infiltration agent (group C) and SIE with In-ceram alumina glass powder as infiltration agent(group D).The surface roughness of specimens in all groups was measured after surface treatments.The surface features of specimens were observed by scanning electron microscopy (SEM),and the changes of surface element contents were detected by energy dispersive spectrometer (EDS).Results The Ra values of surface roughness for groups A,B,C and D were (0.078 0±0.016 0) pμm,(0.100 5±0.003 1) μm,(0.410 7±0.037 0) μm and(0.262 3±0.014 3) μm respectively.The surface roughness in groups C and D was significantly higher compared to groups A and B (all P＜0.01),and there was no significant difference between groups A and B (P＞0.05).The surface roughness in group C was significantly higher than that in group D (P＜0.01),having the highest Ra value of all groups.SEM and EDS revealed the changes in surface morphology but none in contents of surface elements of zirconia ceramics after surface treatments.Conclusion SIE can increase the surface roughness of zirconia ceramics,and shape the reticular gap on surface,which may profit to the infiltration of resin adhesives. Key words: Zirconia ceramics; Selective infiltration etching; Surface treatment; Surface roughness