Effectiveness of Nanohydroxyapatite, Laser, and Plasma on Enamel Remineralization

Objectives: This study aimed to evaluate the efficacy of a commercially available nanohydroxyapatite paste (Nano P), alone and in combination with Air dielectric barrier discharge cold atmospheric plasma (CAP) and a 940-nm diode laser, on enamel remineralization.
Methods: In this in-vitro study, 105 anterior primary teeth were randomly assigned into one control and six experimental groups: (I) control, (II) Fluoride varnish, (III) Nano P, (IV) Nano P + dye + laser, (V) Nano P + laser, (VI) CAP, and (VII) Nano P + CAP. Caries-like lesions were induced by demineralization. Microhardness (MH) was evaluated before and after demineralization and 4 weeks post-remineralization with pH cycling. Data analysis was conducted using One-way ANOVA (α=.05) and Tamhane’s Post-Hoc test, with effect sizes determined by Cohen’s d test and Hedges' g correction.
Results: Initial and secondary MH were similar across groups (P>.05). Post-remineralization, significant differences were observed in compare to control group(P<0.05), with the highest MH in the Nano P + laser group, followed by Nano P + dye + laser, Nano P + CAP, Nano P, Fluoride varnish, CAP, and the control. TIn compare to control, the highest effect size(EF) was found for Nano P+laser (14.6), and the lowest for plasma alone(.1.34). Pairwise comparisons showed significant differences between all pairs except Nano P + laser and Nano P + dye + laser (P=0.7, EF=0.4).
Conclusions: Nano P combined with a laser, was the most effective approach to primary enamel remineralization,followed in order by Nano P with plasma, and Nano P alone. The latter ones significantly increased microhardness more than fluoride or plasma alone, suggesting as effective alternatives for enamel remineralization in primary teeth.