Effect of Acidic Beverages on The Surface Roughness of Glass Ionomers and Glass Carbomer

Objectives: The aim of this in vitro study was to evaluate the effect of acidic beverages (Coke, orange juice and the mixture of orange-pomegranate juice) on surface roughness of glass ionomers and glass carbomer restorative materials.
Methods: In this study four different materials were used: Nanohybrid composite (Z550, 3M-ESPE), resin-modified glass ionomer (Photac-Fil Quick Aplicap, 3M-ESPE), glass ionomer cement (GlasIonomer Type-II, Shofu) and glass carbomer (GCP Glass-Fill, GCP Dental). Discs (n:28, 5x2mm) from each restorative material were prepared according to manufacturers’ instructions. The surfaces of specimens were polished with aluminum-oxide discs and then stored in artificial saliva for 48 hours. The initial roughness measurements of the specimens were obtained from the surfaces and then, they were randomly divided into 4 groups for different acidic beverage applications(n:7). In Group1: specimens were kept in artificial saliva. In Group2: coke (Coca-Cola, Coca-Cola Co.) with pH 2.3, in Group3: orange juice (%100 Orange Juice, Dimes Ltd, Turkey) with pH 3.9 and in Group4: the mixture of orange-pomegranate juice (%100 Pomegranate Juice, Dimes Ltd, Turkey) with pH 3.4 was applied to the specimens.
The samples were immersed into beverages for total 12 hours(3 days, 4 hours per-day). After immersion, surface roughness measurements were obtained from the same surfaces of the specimens at 5 different locations by a stylus-type surface profilometer. The percentage of differences of each specimen between the initial roughnesses and the values after applications were evaluated with two-way ANOVA and posthoc Bonferroni multiple comparisons tests(p<0.05).
Results: In Group1 glass carbomer demonstrated greater roughness change than RMGI and GIC(p<0.05). In coke and orange juice groups glass carbomer had the greatest difference in rouhness than the other materials(p<0.05).
Conclusions: All glass ionomers and glass carbomer were affected by different acidic beverages. In addition, glass carbomer significantly showed the most percentage differences in surface roughness.