Effect of SI-R20401 to remineralize artificial incipient enamel lesions in primary teeth

We evaluated the effectiveness of the experimental surface pre-reacted glass-ionomer coating (SI-R20401) to remineralize artificial enamel lesions in primary teeth. For each of 12 sound primary molars, five regions were assigned, based on whether enamel was unground or ground and whether PRG coating was applied. The teeth were demineralized in 10% EDTA for 7 h and lactic acid solution for 3 days and immersed in artificial saliva (Group 1), demineralizing medium (Group 2) or deionized water (Group 3) for 1 month. DIAGNOdent reading, nanoindentation test and scanning electron microcopy/energy dispersive X-ray analysis were performed. Data were analyzed using analysis of variance and the Fisher protected least significance difference test at α = 0.05. After immersion, a decrease in DIAGNOdent value for the demineralized enamel was observed only in the unground/non-PRG region of Group 1. In the ground/PRG region of Groups 1 and 3, the hardness and Young's modulus at the enamel surface were significantly higher than those at subsurface points. For unground enamel, Ca%, P%, and the Ca/P ratio at the enamel surface of the non-PRG region were significantly lower than those at subsurface points. In Group 2, scanning electron microcopy showed greater demineralization at the unground/non-PRG region compared with the unground/PRG region. Efficacy of SI-R20401 to remineralize the enamel lesions in primary teeth was partially observed, however, to arrest the lesion could not be demonstrated.