Acid Resistance of Glass Ionomer Cement Restorative Materials

Abstract

In view of the need for aesthetics, restorations of teeth will typically be completed using tooth colored restorative materials. With the advent of biomimetic restorative materials, such as glass ionomer cements (GIC), much greater emphasis is now being placed on how well such materials can resist the challenge of acids that are present in foods and drinks, or gastric contents that are regurgitated. This laboratory study compared the dissolution and behavior of five GIC materials (GC Fuji® VII, GC Fuji® Bulk, GC Fuji® IX Fast, Fuji® IX Extra and GC Equia® Forte Fil) when exposed to three acids (citric acid, phosphoric acid and lactic acid), versus ultrapure deionized water, which was used as a control. Discs of each material GIC were submerged in solutions and percentage weight changes over time determined. Subsequently, the GIC materials were also placed as a part of standardized Class II sandwich restorations in bovine teeth (n = 20), and submerged in the solutions, and the extent of GIC dissolution and protection of the adjacent tooth was scored. Weight loss increased with time and with acid concentration. Overall, the most soluble material was GC Fuji® IX Extra, while GC Fuji® IX Fast and GC Fuji® Bulk were less soluble, and the least soluble material was GC Equia® Forte Fil. The most destructive solution for both the discs and for GIC restorations in teeth was 10% citric acid, while the least destructive acid was 0.1% lactic acid. The more recent GIC materials GC Fuji® Bulk and GC Equia® Forte Fil showed increased acid resistance over the older GIC materials, and this further justifies their use in open sandwich Class II restorations in more hostile environments.

Effect of Nano-Filled Protective Coating and Different pH Enviroment on Wear Resistance of New Glass Hybrid Restorative Material

“…Furthermore, the present results also reveal how periodic exposure to a low pH solution alone influences some GIC materials, regardless of the medium in which the samples were stored, and again, Equia Forte HT performed better. This is in agreement with Perera et al [47], finding that the more recent GIC materials (GC Fuji Bulk and GC Equia Forte Fil) showed increased acid resistance over the older GIC materials, including Fuji IX. The enhanced formulation of the new generation highly viscous GICs and glass hybrid materials increases strength and acid resistance [47].…”

“…This is in agreement with Perera et al [47], finding that the more recent GIC materials (GC Fuji Bulk and GC Equia Forte Fil) showed increased acid resistance over the older GIC materials, including Fuji IX. The enhanced formulation of the new generation highly viscous GICs and glass hybrid materials increases strength and acid resistance [47].…”

Influence of pH Cycling on Erosive Wear and Color Stability of High-Viscosity Glass Ionomer Cements

“…Furthermore, this research study showed that the mass of samples in all three materials decreased significantly more if exposed to Aceto balsamico vinegar than to Fuzetea and distilled water ( p < 0.05). This is in concordance with Perera et al’s report [ 16 ] and suggests that the availability of hydrogen ions (pH) is related to the extent of a material’s dissolution and disintegration. However, there was no statistically significant difference among the three groups of materials in certain pH environments ( p > 0.05).…”

“…Exposing standardized GIC samples to acidic load and assessing the change in mass has been well established in previous studies as the method for testing the resistance of GICs to acid [ 15 , 16 ]. The conditioning period of one week at 37 °C allowed stabilization of the acid–base reaction of glass ionomer cements so that water uptake would not affect the mass recordings because it was shown that hygroscopic expansion of GICs occurred in the first 24 h [ 22 , 23 ].…”

“…The disintegration of restoration due to erosion leads to mass reduction, and rough surface of the material with microcavities and protruded, partly decomposed glass particles which favors staining and discoloration [ 10 ]. Therefore, it is very important to consider the resistance of a material to acidic load when assessing its suitability for restoration in certain clinical situations, such as class II open-sandwich restorations, especially in patients with a history of gastroesophageal reflux disease, eating disorders or consuming much acidic beverages and acidic foods [ 10 , 13 , 16 ].…”