Exploring the potential of bioactive composites on the inhibition of enamel demineralization

Abstract

Objective: This work investigated the ion release from an experimental composite containing dicalcium phosphate dihydrate (DCPD) and a commercial composite containing ion-releasing particles, assessing their effectiveness in inhibiting enamel demineralization in vitro. Material and Methods: Ion release of calcium and phosphate was determined by inductively coupled plasma emission spectroscopy, while fluoride release was determined with an ion-specific electrode. Enamel specimens from bovine incisors were prepared measuring 6 x 6 mm and randomly distributed into three groups according to the restoration performed in their central portion into 3 groups (n=15): DCPD composite group (experimental composite); Giomer group (commercial composite Beautifil II®, Shofu), or a control group (Z250®, 3M ESPE). Samples underwent pH cycling in a remineralizing solution (20h) and a demineralizing solution (4h) for 8 days. Enamel surface hardness was evaluated at baseline (SH) and after the experiment (SH1), with transverse hardness measured post-pH cycling using a microhardness tester (25 g for 10 s). Surface hardness loss (%SHL), transverse hardness and integrated mineral loss (ΔKHN) were calculated. Data were analyzed by one-way ANOVA/Tukey test (alpha: 0.05). Results: DCDP group showed significantly higher calcium and phosphate concentrations, while Giomer group had higher fluoride, aluminum, boron, sodium, silicon and strontium concentrations compared to the control in both solutions. Giomer group demonstrated significantly less %SHL compared to Z250 group but was comparable to DCPD group. Only Giomer group effectively inhibited enamel surface demineralization, while both DCPD and Giomer group partially prevented subsurface demineralization. Conclusion: These findings suggest that incorporating DCPD into composites may enhance their protective effects against enamel demineralization, providing valuable insights for clinical applications in restorative dentistry.

KEYWORDS

Bioactive materials; Composite resins; Demineralization; Dental caries; Remineralization.