Long-term evaluation of the remineralization of interproximal caries-like lesions adjacent to glass-ionomer restorations:: A micro-CT study

Purpose: To compare the remineralization of incipient artificial interproximal caries in the presence of three glass-ionomer cements (highly-filled glass-ionomer cement, compomer, resin-modified glass-ionomer cement) and a resin composite (control). Methods: Proximal restorations were simulated by placing tooth specimens and the various glass-ionomer cements in closed containers with artificial saliva at 37 degrees C and pH 7.0 for 30 days with constant circulation. Tomographic images were obtained with a micro CT scanner at 90, 180, and 270 days, and density-measuring software was used to calculate the micro-density of artificial caries lesions in the specimens. The mean density changes were compared between groups in order to evaluate the effects of remineralization. All data were analyzed using one-way ANOVA and the post-hoc Tukey multiple comparison test at P<0.05. Results: While the density of artificial caries lesions increased for all treatments, the increases for the three glass-ionomer groups were significantly higher than that for the resin group in each 3-month period. As time increased, the amount of density also increased for the glass-ionomer groups, and significant differences were found between the remineralization effects of the glass-ionomer groups. The micro CT proved to be an effective evaluation method.