Influence of Kinetic Cavity Preparation Devices on Dental Topography: An in vitro Study

Abstract

The objectives of this study were to assess the influence of four different kinetic cavity preparation devices on cavity preparation taking into account tip angulation, internal tip diameter, and distance to the dental substrate. The dental topography itself was also evaluated after the use of these devices. Quantitative parameters using pertinent statistical tests as well as qualitative parameters were used to assess the topography in terms of the dispersion halo effect (DHE), size, and depth of the preparation. The DHE did not present differences among the groups. In relation to the preparation size, the internal diameter influenced 120 masculine point angles, whereas distance influenced the 90 masculine ones. Considering the preparation depth, the 90 degrees point angle yielded the deepest. In the qualitative analysis, both angles provided cavity preparations with rounded cavosurface angles. The 120 masculine point angles yielded inclined, shallow V-shaped preparations, whereas the 90 masculine angles presented U-shaped preparations reaching the dentin. The enamel had an irregular aspect and exposed prisms; dentin had a loose smear layer with aluminum oxide residues. The kind of device may influence the kinetic cavity design. It is the clinician that knows how to select the appropriate devices to adopt in order to achieve the desired cut, depth, and shape of cavity preparations.