University of Kashan Journal of Nanostructures 2251-7871 13 2 2023 04 01 Influence of Various Polishing Systems on the Surface Roughness of Nanofilled Composite Resin: A Comparative in Vitro Study 553 558 114281 10.22052/JNS.2023.02.025 EN Tay Hatem Kadhom M.Sc. in conservative and aesthetic dentistry/Department of university healthcare /Al-Nahrain university, Iraq tayhatim212@gmail.com Journal Article 2023 01 05 This study aimed to assess and compare the surface roughness of nanofilled resin based composite (Filtek Z-350 XT) after using different finishing-polishing systems. sixty disk shaped samples were made from resin composite by using standardized cylindrical metal mold with measurements of 2 mm in thickness and 10 mm in diameter. The samples were randomly assigned to six experimental groups (number = 10): group 1 (transparent Mylar strip), group 2 (Sof-Lex discs), group 3 (Super-Snap discs), group 4 (OptiDisc discs), group 5 (Opti1Step polishers) and group 6 (OneGloss polishers). For each sample, the mean value of average surface roughness (Ra) was defined after three-times measurements using a profilometer. Depending on the results of ANOVA test, the surface roughness of the evaluated groups was in the following arrangement: transparent strip < Super Snap discs < OptiDisc discs < Opti1Step polishers < SofLex discs < OneGloss polishers. The difference was statistically significant for composite surface roughness in the six study groups (P < 5%). The surface finish of Filtek Z-350 XT nanofilled composite was found to be influenced by the following factors: composition of the finishing-polishing system used, number of polishing steps, in addition to the flexibility of the system during execution of finishing and polishing procedures. https://jns.kashanu.ac.ir/article_114281_2df88a37fe188c8196847c14252eee2e.pdf