Finishing And Polishing Of A Small-Particle Hybrid Composite M. Jung* And M. Brandt (Dental-Clinic; Justus-Liebig-University; Giessen; Germany) Flexible discs are generally accepted as a standard for polishing of smooth composite surfaces. With increasing use of composites for the restoration of posterior teeth, different techniques for polishing of structured surfaces are necessary. The objective of our study was to evaluate three finishing methods together with six alternative methods for polishing of a hybride composite.   Totally 95 specimens being 7x7x4 mm in size were made of the composite Herculite XRV®. Five specimens each pretreated by finishing either with a 30 µm diamond, a sequence of two diamonds (30/20 µm grit size) or a 30 µm diamond followed by a 16-fluted carbide bur were subsequently polished using six different methods: Shofu CompoSite, HaWe Composite Polishers, HaWe Okklu-brush, diamond and silicon carbide rubber polishers (Brasseler) and diamond impregnated felt wheels (Müller Dental). 5 additional specimens were polished by Sof-Lex discs (3M). Surface roughness was evaluated using a Focodyn laser pick-up under the following conditions: transverse length LT = 1.75 mm; 9 scans per surface; cut-off lC = 0.25 mm).   Average roughness Ra was calculated; the results were statistically analysed by one-way Anova and Tukey post-hoc tests.   Statistics revealed an effect of the finishing method (p = 0.03) on the surface roughness and significant differences between the polishing methods tested (p < 0.001). The lowest Ra-values were caused by the diamond impregnated felt wheels (Ra = 0.53 µm after finishing with a diamond followed by a carbide bur and Ra = 0,56 µm after finishing with two diamonds). These surfaces were smoother than those polished by Sof-Lex discs (Ra = 0.62 µm). All the other polishing methods caused Ra-values greater than those by Sof-Lex discs.   It can be concluded, that the finishing method must be carefully selected with respect to the polishing method used. Under the conditions of this study only the use of diamond impregnated felt wheels achieved lower roughness values than Sof-Lex discs.