Study of the chemical interaction between a high-viscosity glass ionomer cement and dentin

Abstract

Objective To investigate the chemical interactions between a high-viscosity glass ionomer cement (GIC) (KetacTM Molar Easymix, 3M ESPE, Seefeld, Bavaria, Germany) and human dentin. It was also analyzed the dynamics of GIC setting mechanism based on the time intervals required for the GIC and the GIC mixed with dentin to achieve stability.Material and Methods Each constituent of GIC – powder (P) and liquid (L) – and powdered dentin (D), as well as the associations P+L, D+L, and P+L+D in the concentrations of 29%, 50%, 65%, 78%, 82%, and 92% of GIC were analyzed with Fourier transform infrared (FTIR) and Raman spectroscopy.Results New optical absorption bands and/or Raman bands, which were not present in P, L, or D, were observed in the associations. The concentrations of 29% and 50% of GIC showed higher interaction, revealing that the amount of dentin influences the formation of new optical absorption or scattering bands. FTIR bands showed that the setting time to achieve bond stability was longer for the high-viscosity GIC (38±7 min) than for the sample with 29% of GIC (28±4 min).Conclusions The analysis revealed the formation of new compounds or molecular rearrangements resulting from the chemical interactions between GIC and dentin. Moreover, this study provides an effective method to evaluate the dynamics of the setting mechanism of GICs.

Maturation processes in glass-ionomer dental cements

“…X-ray photoelectron spectroscopy is a high vacuum technique that does not allow clinically realistic conditions to prevail. However, more recently it has been confirmed that glass-ionomers undergo a chemical reaction with the mineral phase of teeth, using FTIR to study the reaction that occurs when ground tooth material was added to glass-ionomer dental cements [ 56 ]…”

Proximal retention grooves may increase early fracture strength of ART restorations

“…Study with Fourier transform infrared (FTIR) and Raman spectroscopy has shown that the setting time to achieve bond stability of GIC with dentin was longer for the high-viscosity GIC (38±7 min) than for the sample with 29% of GIC (28±4 min) [13]. In this work the matrix was maintained for both materials for 6 minutes and removed carefully.…”

“…Another aspect of extreme importance in the restorative technique is the time that must be waited until the initial hardening of the material to start finishing and expose GIC in contact with water [13]. Works on the ART technique do not mention the maintenance time [14,15] or when it is mentioned, it is below the setting time mentioned on the manufacturer's instructions [8,16].…”

“…Works on the ART technique do not mention the maintenance time [14,15] or when it is mentioned, it is below the setting time mentioned on the manufacturer's instructions [8,16]. It is also of utmost relevance the matrix removal to guarantee the stabilization of the GIC setting reaction and the bonding of the material to the dental structure [13]. In this study we waited 6 minutes for both materials.…”

Correlation between mechanical properties and stabilization time of chemical bonds in glass-ionomer cements

“…Yamakami et al 6 recently proposed to analyze the dynamics of GIC setting mechanism based on the time intervals required for the GIC to achieve stability. The setting time or hardening time (in minutes) of a material presented in the package by the manufacturer is different from the time to reach complete reaction or chemical bonds stability (stabilization time) 6 . From the clinical point of view, this information is important because the time for stabilization of chemical bonds can influence mechanical properties of GICs and restoration longevity.…”