Remineralization capacity of carious and non-carious white spot lesions: clinical evaluation using ICDAS and SS-OCT.

Abstract

To assess the remineralization capacity of carious, non-carious, and combined white spot lesions (WSLs) using the ICDAS and SS-OCT. This clinical trial was based on a quasi-experimental design. Forty-two healthy subjects (median age 26.6years), who visited university hospital and had at least one WSL with an ICDAS score of 2 or 1, were recruited. The subjects chewed a non-blind sugar-free gum containing bioavailable calcium and fluoride for 3months. The remineralization capacities of carious and non-carious 121 WSLs were assessed using ICDAS by two calibrated non-blind examiners and optical boundary depth (BD) by SS-OCT at a monthly recall. The outcome variables, transitions of ICDAS score, mean BD, and mean BD recovery rate (RR%), were statistically analyzed using the chi-square test, two way-repeated measures ANOVA, and Wilcoxon rank sum test, respectively (alpha = 0.05). Based on the visual inspection, OCT images at the baseline, 72 WSLs were purely carious, 20 were non-carious (developmental) lesions, while 29 were combined (carious-developmental). The responses of WSLs over time showed to be highly variable. There was a significant difference in transitions of ICDAS scores after 3months between carious and non-carious WSLs (p < 0.05) and non-carious and combined WSLs (p < 0.05). Carious and combined WSLs underwent significant changes in the mean BD between baseline (161.8 ± 56.8μm) and 2months (130.7 ± 57.4μm) or 3months (119.1 ± 57.5μm) (p < 0.05), while there was no significant difference between baseline (132.2 ± 26.2μm) and 2months (122.8 ± 24.1μm) or 3months (119.8 ± 22.6μm) in non-carious WSLs (p > 0.05). There was a significant difference in mean RR% after 2 and 3months between carious and non-carious WSLs (p < 0.05). The remineralization capacity of WSL was variable among the cases and subjects, and depended on the WSLs history, etiology (carious, non-carious, or combined lesion) and structure (histological pattern). Carious WSLs showed the highest remineralization potential.