Application of atomic force microscopy in investigations of dental alloy surfaces

Introduction. The aim of this informative paper is to show the importance and key role of atomic force microscopy, on one hand, in quantitative determination of the physicochemical changes on the surfaces of dental materials due to their exposure to acids and, on the other hand, in quantification of changes in the physicochemical properties of the surfaces of dental alloys after their processing and the consequences of the processing itself on the quality and applicability of the same. Methods. Atomic force microscopy was used to obtain data quantitatively describing nanoscale changes in Co-Cr dental alloys caused by exposure to formic acid over a 7-day period and to describe the effects of electropolishing and black brush polishing on the surface roughness of dental alloys. Results. Analysis of the topography and roughness of the surfaces of alloys treated with a black brush and electropolishing shows that both methods are applicable in dentistry and leave defects of insufficient size for microorganisms. Treatment of the studied alloys with formic acid leads to an increase in surface roughness, indicating the presence of corrosion processes, especially in the areas of interdentritic nanocrystals. Conclusion. The aforementioned effects of processing and treatment of Co-Cr alloys can be followed in great detail using the technique of atomic force microscopy, especially by analysing the surface topography and its roughness. The method is of extraordinary importance for the evaluation of the use of Co-Cr alloys in dentistry.