Int J Prosthodont 33 (2020), No. 2 9. Mar. 2020
Int J Prosthodont 33 (2020), No. 2 (09.03.2020)
Page 217-223, doi:10.11607/ijp.6686, PubMed:32069347
The Effect of a Polishing Protocol on the Surface Roughness of Zirconium Oxide
Linkevicius, Tomas / Valantiejiene, Valda / Alkimavicius, Jonas / Gineviciute, Evelina / Andrijauskas, Rolandas / Linkeviciene, Laura
Purpose: To evaluate the surface roughness values of zirconium oxide samples that were gradually polished using a commercially available polishing system and polishing paste.
Materials and Methods: A total of 50 rectangular specimens of predetermined size (10 × 10 × 3 mm) were sintered from zirconium oxide. Samples were randomly assigned to one of five groups (n = 10 each): control, coarse (Co), fine (F), super fine (SF), or polishing paste (PP). In the control group, no polishing was done; in the Co group, a coarse polisher was used; and the specimens in the remaining three groups underwent additional processing with a fine rubber abrasive. For SF and PP samples, subsequent treatment with a super fine polisher was applied. Finally, for the PP group, a goat-hair brush with diamond polishing paste was used. An optical profilometer was used to evaluate roughness average (Ra) in micrometers (μm). ANOVA and Games-Howell post hoc tests were utilized to detect differences between groups. The significance level was set to α = .05.
Results: Surface roughness gradually decreased with further polishing throughout the groups: control Ra = 0.525 ± 0.099 μm; Co Ra = 0.252 ± 0.038 μm; F Ra = 0.196 ± 0.035 μm; SF Ra = 0.114 ± 0.031 μm; and PP Ra = 0.054 ± 0.020 μm. Statistically significant differences were detected among all groups (P < .05).
Conclusion: A surface roughness of 0.054 μm can be achieved if a full zirconia polishing protocol is used. Zirconium oxide can be polished to various surface roughnesses using commercially available polishing products.