Abstract
Objectives: This in vitro study aimed to evaluate the effect of resin infiltration combined with casein phosphopeptide-amorphous calcium phosphate with fluoride (CPP-ACPF) or bioactive glass (BAG) on the stability of enamel white spot lesions (WSLs) treatment. Materials and methods: Eighty-four enamel blocks were prepared from the buccal surfaces of sound human premolars. All enamel blocks were placed in a demineralisation solution for 3 days to establish the artificial enamel WSLs. Enamel blocks with WSLs were randomly divided into three groups ( n = 28 each group): RI/B: one-off resin infiltration followed by twice daily BAG treatment; RI/C: one-off resin infiltration followed by twice daily CPP-ACPF treatment; RI: one-off resin infiltration treatment only (as control) and subjected to pH cycling for 7 days. Surface morphology, elemental analysis, crystal characteristics, surface roughness and microhardness of enamel surfaces were investigated by scanning electron microscopy and energy-dispersive spectrometry observation, X-ray diffraction (XRD), atomic force microscope and Vickers ' hardness testing, respectively. Results: Mean values of the surface roughness (mean +/- standard deviation (nm)) were 24.52 +/- 5.07, 27.39 +/- 5.87 and 34.36 +/- 4.55 for groups RI/B, RI/C and RI respectively ( p = 0.003). The calcium to phosphate ratios were 1.32 +/- 0.16, 1.22 +/- 0.26 and 0.69 +/- 0.24 for groups RI/B, RI/C and RI respectively ( p < 0.001). XRD revealed apatite formation in all three groups. The mean enamel surface microhardness (kg/mm 2 ) of the groups were 353.93 +/- 28.49, 339.00 +/- 27.32 and 330.38 +/- 22.55 for groups RI/B, RI/C and RI respectively ( p = 0.216). Conclusions: Resin infiltration combined with CPP-ACPF or BAG remineralisation appears to improve the surface properties of WSLs. Clinical Significance: The combination of resin infiltration and CPP-ACPF/BAG remineralisation may be a potential treatment for the management of the WSLs.