Effect of surface treatments on color of machinable ceramics

Salem, Amna; Mohsen, Cherif

doi:10.21608/jmr.2020.29066.1025

Effect of surface treatments on color of machinable ceramics

Document Type : Original Article

Authors

Amna Salem ¹
Cherif Mohsen ²

¹ Department of Fixed Prosthodontics, Faculty of Dentistry, Assiut University, 71515 Assiut, Egypt

² Department of Fixed Prosthodontics, Faculty of Dentistry, Minia University, 61519 Minia, Egypt

10.21608/jmr.2020.29066.1025

Abstract

Aim: The purpose of this study is to evaluate the effect of surface treatments on color of lithium disilicate ceramic (IPS e. max [CAD]) and hybrid ceramic (VITA Suprinity [pc]).
Method: Ceramic blocks were sectioned in to one hundred sixty discs; eighty discs of lithium disilicate were randomly subdivided in to four groups according to surface treatment (n= 20). Group C: Control group without surface treatment; group I: using (AL2O3) particles size 50µm; group II: Hydro fluoric (HF) acid etching; group III: tribochemical (TBC) surface treatment. Eighty discs of hybrid ceramic (n= 20) were subdivided in to the same groups. Color measurements were performed with spectrophotometer and repeated after surface treatments. ∆E values were statistically analyzed with one- way ANOVA, Tukey's post hoc test was done to identify significance between groups. Statistically significance was considered when P value ≤ 0.05.
Results: Changing color of lithium disilicate specimens were not clinically perceptible except for hydrofluoric acid etching as it was below the clinically accepted threshold (∆E < 2.7). Suprinity hydrofluoric acid etching specimens color changes were clinically acceptable ∆E < 2.7 but air abrasion with Al2O3 50 µm and tribochemical surface treatment specimens showed ∆E > 2.7 which were clinically unaccepted.
Conclusion: Different techniques; sand blasting, HF acid etching and tribochemical surface treatments affected color significantly.

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