Crystal growth by restorative filling materials

Abstract

This study examined the activity and ability of materials to mineralize teeth in gaps, simulating microleakage between the materials and teeth. Three restorative materials (two glass ionomer cements and a compomer) were used in this study. Cured disks of restoratives were placed over flat human tooth surfaces (enamel and dentin), separated by a standardized 20-μm interfacial space, and stored in water for 24 h or 1 yr. After the water-storage period, the materials were detached from the teeth and the opposing surfaces were examined by scanning electron microscopy (SEM) and electron probe micro analysis (EPMA).Hemispherical-shaped precipitations, composed of minute semicircle plate-like crystals, were observed by SEM on the enamel surface after 1 yr of water storage for glass ionomer cement. The amount of crystal growth with the chemical-cured type of glass ionomer cement was greater than with the dual-cured type of glass ionomer cement. However, there was no crystal formation in the compomer. Moreover, no structural changes were observed on dentin surfaces for any material in water after 1 yr. The elements detected in the crystals by EPMA were calcium (Ca), phosphorus (P), and aluminum (Al). The two glass ionomer cements tested have the ability to induce crystals whose composition might be derived from cured glass ionomers.

Calcium phosphate precipitation in experimental gaps between fluoride‐containing fast‐setting calcium silicate cement and dentin

“…We did not observe any precipitates at the gap entrances in the resin‐modified glass ionomer groups. These observations are in agreement with a study demonstrating that GC Fuji II LC did not encourage crystal growth over dentin in gaps with 20 μ m thickness, even after 1 year . In general, resin‐modified glass ionomers cause an acidic pH after mixing and over time .…”

The effect of dentine pre-treatment using bioglass and/or polyacrylic acid on the interfacial characteristics of resin-modified glass ionomer cements

“…Moreover, since GIC-based materials have the aptitude to induce crystal growth 22 within the interface of the restoration after long-term storage in water, with a chemical composition similar to that of dental hard tissues 23,24 , it is hypothesised that the combination of dentine pre-treatment with BAG air-abrasion and subsequent restoration using GIC-based materials could be a suitable strategy to achieve longer-lasting bonding interfaces that can resist degradation over time.…”

Influence of air‐abrasion executed with polyacrylic acid‐Bioglass 45S5 on the bonding performance of a resin‐modified glass ionomer cement

“…Indeed, the finding that this layer did not absorb water further after 6 months of storage in PBS (Fig. 2) may be the result of a process of crystallization occurring over time, particularly in the presence of biological fluids (12,13,22). This process is also known as maturation, which begins with an acid-base reaction initiated with depletion of metallic ions from the FAS glass by polyalkenoic acid and leaving siliceous hydrogel layers on the surface of the glass particles (27,28).…”

“…Studies have demonstrated the ability of glass ionomer cements (GICs) to induce crystal growth in microspaces within the interface of the restoration after long‐term storage in water (12, 13), and the chemical composition of these crystals is similar to that of dental hard tissue (14, 15). Although GICs may have reduced mechanical characteristics (i.e.…”