The effect of different re-mineralizing agents and diode laser irradiation on the microhardness of primary molar enamel: An in vitro study

Background and Aims: Dental caries is a global concern and different materials and methods were proposed for its prevention. The aim of this study was evaluation of the effect of different demineralizing agents with and without diode laser radiation on the microhardness of primary molars enamel. Materials and Methods: 48 primary molar teeth were used in this study. The enamel blocks were prepared. Primary microhardness values were also measured. All samples were demineralized, then demineralization was approved by a DIAGNOdent pen. The remineralization was done into the buccal and lingual surfaces of the samples as follows: Group 1: CPP-ACP, Group 2: CPP-ACPF, Group 3: MI varnish, Group 4: NaF varnish. The lingual surfaces received diode laser irradiation. Finally, a secondary microhardness test was performed on all samples. Statistical analyses were done and a P-value less than 0.05 was considered to be statistically significant. Results: A comparison between the primary and the secondary microhardness values showed significant differences (P = 0.003). The highest secondary microhardness values belonged to the MI varnish +laser group. Conclusion: Application of the agents, containing the combination of Ca, P, and F, was significantly better than others in increasing the microhardness of the enamel. Although the application of diode laser increased the hardness of the enamel.