Investigation of the surface of light-curing dental materials after pre-polymerization heating

Abstract

Despite the great variety and wide application of light-cured composite restorative materials for the treatment of hard tissue diseases, the issue of longevity of restorations remains relevant to this day. One of the criteria for the long-term durability of a composite restoration is the finish of the restoration. Poor polishing and surface roughness significantly reduce theservice life of the restoration and provide a good environment for biofilm adhesion, loss of luster of the restoration, and caries recurrence. Thus, methods affecting the reduction of surface relief in restorations remain a current issue. Aim. To evaluate the surface roughness and porosity of composite filling materials after pre-polymerization heating. Materials and methods. Sixty composite samples were prepared in the form of 1 mm thick, 1.2 cm diameter disks. The samples were divided into 2 groups depending on the presence of pre-polymerization heating. Atomic force microscopy (AFM) was used to measure the roughness and to visualize the surface morphology of the samples. Porosity was measured using a vacuum sputtering unit, and a scanning electron microscope was used to obtain micrographs of the sample. Results. The use of pre-polymerization heating of composite filling materials in dental practice will allow dentists to significantly reduce the expression of the relief of the composite restoration by reducing the roughness and pore volume in the matrix of the composite filling material, which will certainly optimize the finishing of the restoration. Conclusions. Pre-polymerization heating has a positive effect on the surface topography of the composite restoration, reducing its roughness and porosity, which improves the stage of finishing: obtaining a dry gloss, ensuring the duration of color stability, as well as reducing the adhesion of microorganisms to the filling material, thereby increasing the longevity of the composite restoration.