Kinetics of ion release from a conventional glass-ionomer cement

Abstract

Release kinetics for sodium, silicon, aluminium, calcium and phosphorus from conventional glass-ionomer dental cement has been studied in neutral and acid conditions. Specimens (6 mm height × 4 mm diameter) were made from AquaCem (Dentsply, Konstanz, Germany), 6 per experiment. They were matured (37 °C, 1 h), then placed in 5 cm3 storage solution at 20–22 °C. In the first experiment, deionised water, changed daily for 28 days, was used. In the second, deionised water, changed monthly for 21 months, was used. In the third, lactic acid (20 mmol dm−3, pH: 2.7 ± 0.1), changed monthly for 21 months was used. After storage each solution was analyzed by inductively coupled plasma-optical emission spectroscopy (ICP-OES). Results showed that in neutral conditions, no calcium was released, but in acid, significant amounts were released. The other elements (Na, Al, Si and P) were released in neutral as well as acid conditions, with greater amounts in acid. More frequent changes of water gave greater release. In neutral conditions, release over 21 months followed the equation: [E]c = [E]1t/(t + t½) + β√t ([E]c is the cumulative release of the element). In acid conditions, this became: [E]c = [E]1t/(t + t½) + αt. Hence release of all elements was shown to occur in two steps, a rapid initial one (half-life: 12–18 h) and a longer second one. In neutral conditions, the longer step involves diffusion; in acid it involves erosion. These patterns influence the material’s bioactivity.

Multivalent network modifier upregulates bioactivity of multispecies biofilm-resistant polyalkenoate cement

“…3 C and Figure S4 ). The elution behavior (with solution refreshing at regular intervals) showed the release pattern similar to findings from earlier studies [ 40 ]. The observation of release profile suggested an initial rapid release followed by reduction to a plateau after 72 h. A close to total release around day 7 followed by reduction below the detection level while nearing two-weeks was observed.…”

“…The tubes were sealed and incubated at 37 °C, in adherence to an earlier protocol [ 71 ]. To assess the cumulative ion release, the elute media was collected progressively at different time points (1, 3, 7, 14, 21 days) and the solution was regularly refreshed [ 40 ]. The elution was stored at 37 °C in sealed tubes prior to elemental analysis using an inductively coupled plasma optical emission spectrometer (ICP-OES, Agilent 5100, Agilent Technologies, CA, USA).…”

Monomer Conversion, Dimensional Stability, Biaxial Flexural Strength, Ion Release, and Cytotoxicity of Resin-Modified Glass Ionomer Cements Containing Methacrylate-Functionalized Polyacids and Spherical Pre-Reacted Glass Fillers

“…The most attractive property of glass ionomer cements is their ability to release fluoride. It is expected that the sustained release of fluoride at a low concentration could potentially help promote the remineralization of the demineralized tooth minerals [ 56 ]. However, the minimum level of fluoride release required to promote a significant clinical benefit has not yet been established by the ISO standards [ 57 ].…”

Polybetaine-enhanced hybrid ionomer cement shows improved total biological effect with bacterial resistance and cellular stimulation

“…30 The ion-release behavior of ionomer cements during immersion in different media over varying periods has been studied extensively. 31 Their acid neutralization response is also well documented and is responsible for their high biocompatibility. 7 Previous studies have also explored the role of polybetaines in aiding the neutralization of bioactive resin formulations and have attributed it to enhanced ionic exchange from the bioactive filler.…”

“…Moreover, the secondary phase is affected by the pH and is slower under neutral conditions. 31 Therefore, it is possible that the contrasting gene expression trends observed in this study are related to the augmented ion release with the addition of α-mZM.…”