In vitro evaluation of the effects of various remineralization agents in root caries

The aim of this study was to compare the effects of different fluoride varnishes on artificial root caries lesions and biofilm formation. Bovine root dentin specimens (n=138) were prepared and demineralised for 5 days. Dentin blocks randomly allocated to 6 groups (n=23/group): (1) untreated control, (2) Sodium Fluoride (NaF), (3) NaF+ Casein Phosphopeptide-stabilized Amorphous Calcium Phosphate complexes (CPP-ACP), (4) NaF+ Tricalcium Phosphate (TCP), (5) NaF+ Xylitol-coated Calcium and Phosphate (CXP) and (6) Silver Diamine Fluoride/Potassium İodide (SDF/KI). Specimens spared for spectral analysis (n=15) were subjected to pH cycling for 8 days. Before and after ph cycling, FTIR-ATR and Laser Fluorescence were used to detect changes in organic/inorganic content. S. mutans and L. casei dual-species biofilm were performed on artificial caries lesions treated with remineralization agents (n=8). Bacterial biofilm formation was evaluated with CLSM and SEM. The obtained data was analyzed with SPSS version 25.0. The results were evaluated at p<0.05 significance level. According to the results of LF, SDF/KI showed maximum remineralization values after pH cycling. All treatments reduced LF values significantly compared with control group. FTIR-ATR showed chemical reactions within dentin tissue in SDF/KI group. A significant difference in decrease of hydrogen phosphate-to- amide I ratio observed mostly in control group other than four test groups. CLSM analysis showed that all varnishes are effective on total and viable biomass. However NaF was the most effective material against biofilm formation. Application of varnishes reduced the biofilm formation and demineralisation of root caries.