The Effects of Root Demineralization Inhibition by a Glass Ionomer Cement Containing Zinc Glass

Abstract

 Purpose: The purpose of this study was to investigate the effects of a newly-developed glass ionomer cement containing zinc glass on the demineralization inhibition and the remineralization of root dentin for the treatment of root caries.

 Materials and Methods: Three chemical-set glass ionomer cements, ZIF-C10 (GC) containing zinc glass, Fuji VII (GC) and GlasIonomer FX ULTRA (Shofu), were set to the root dentin before or after the demineralization to evaluate the demineralized inhibition and remineralization effects. For the demineralization inhibition test, transmitted X-ray images were obtained by micro focus X-ray CT. Mineral profiles of root dentin up to 200 μm in depth were obtained from the images to analyze the mineral loss (vol %・μm). For the remineralization test, each material was filled in the pre-demineralized dentin cavity to simulate root caries. Cross-sectional images of the cavity after the remineralization for 60 days were taken using swept-source optical coherence tomography (SS-OCT). The area of interest near the cavosurface margin for 400 μm in width and 400 μm in depth was chosen to analyze the integrated intensity and attenuation coefficient of the SS-OCT signal. Image analysis was performed using ImageJ.

 Results: The results of the demineralization inhibition test showed a significant decrease of mineral loss for all the glass ionomer cements compared with the control. The amount of mineral loss for ZIF-C10 was significantly lower than those of the other glass ionomer materials (p<0.05). The SS-OCT signal of demineralized dentin after the remineralization test showed a significant decrease of integrated signal for ZIF-C10. The attenuation coefficient (μt) of SS-OCT signal intensity for ZIF-C10 was significantly lower than those of other materials (p<0.05).

 Conclusion: The results of this study suggest the superior demineralization inhibition and remineralization effects on root dentin of the newly-developed glass ionomer cement containing zinc glass.