The effect of different solutions on the surface structure and solubility of current posterior composites

Aim: The aim of our study was to evaluate the effects of different acidic liquids taken into the oral environment as a result of daily routine nutrition on the surface properties and solubility of current composites used in posterior restorations, using Atomic Force Microscopy (AFM) and Scanning Electron Mycroscope-SEM. At the same time, it is to detect the loss of solute with the use of precision balances. Material and Method: In our study; one microhybrid Clearfıl Majesty Posterior ( Kuraray , Okayama, Japan ) composite resin one supra-nano hybrid Estelıte Sıgma Quıck (Tokuyama, Tokyo, Japan) composite resin, one microhybrid composite resin G-Aenial Posterior (GC Corporation, Tokyo, Japan) Three different brands of composite resin materials, which are frequently preferred in Restorative Dentistry, were used. All composite samples were polymerized in plastic molds with a depth of two mm and a diameter of eight mm, in line with the recommendations of the manufacturer, and prepared in a total of 84 pieces. The solutions in which the composite resins will be kept were determined as 15% tartaric acid, 85% lactic acid and 10% citric acid and distilled water; the samples were kept in four different liquids for seven days. In order to determine the water solubility levels of the composite disc samples prepared in our study, the standard formula reported in the ISO 4049:2009 specification was taken as basis. The surface roughness values of the samples were measured with the AFM ; the roughened surfaces were visualized with the SEM . Results: In our study using AFM and SEM, the lowest initial/final surface roughness value was observed in the material of the G-eanial posterior composite resin group. Although all composite resin materials used are affected by the solutions, the solubility value of Clearfıl Majesty Posterior composites kept in lactic acid and tartaric acid solution was found to be meaningfully higher than Estelite Sigma Quick and G-Aenial Posterior composites. (p<0.005) Conclusion: The oral cavity is a complex environment where different intrinsic and extrinsic factors can compromise the aesthetics, function and longevity of restorative materials. In this respect, "nutrition habits", which have an important share, cause solubility and surface structure changes on composite resins. It was observed that all composite resin materials we used in our study were affected by acidic liquids at different rates in terms of surface roughness and solubility.