الفهرس 
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Abstract
Abstract : Objectives : To evaluate the effect of different finishing/polishing systems on surface roughness and microhardness of an ormocer-based and two different resin-based composite restorative materials. Materials and methods : A total number of 135 disc-shaped specimens of an ormocer-based composite; Admira® Fusion x-tra, a nanohybrid resin composite ; Tetric N ceram®, and a nanoceramic resin composite; Ceram.x® SphereTEC™ one (n = 45 each) were fabricated using a cylindrical mold (10 mm diameter x 2 mm thickness). The specimens were prepared against polyester strips and glass slides from both sides. All materials were used and manipulated according to manufacturers’ instructions. Nine specimens from each material group didn’t receive any surface treatment to act as a negative control subgroup. The remaining specimens were finished using diamond finishing abrasive. All the finished specimens of each material group were randomly assigned to four subgroups (n = 9). One of them was used as a positive control subgroup. The remaining three subgroups were subjected to additional finishing/polishing techniques with either, multiple-step (Sof-Lex), two-step (Politip), or one-step (PoGo) systems. All specimens were stored in double-distilled water at 37oC for one week, then subjected to qualitative and quantitative assessment of surface roughness using 3D surface analyzer system, followed by microhardness measurement using Vickers microhardness tester. The collected data of each test were coded and statistically analyzed using two-way analysis of variance (ANOVA) followed by post-hoc Tukey multiple comparisons. Results : The outcome of two-way ANOVA revealed that the type of composite material and finishing/polishing techniques had statistically significant effects on the results of surface roughness and microhardness (p < 0.05). Furthermore, the interaction between the two variables was significant (p < 0.05). Post-hoc Tukey test outcome showed that ormocer-based composite subjected to one-step polishing system exhibited higher surface smoothness and microhardness values than resin-based composites subjected to the other investigated finishing/polishing systems. Conclusion : Surface roughness and microhardness were affected by both the type of composite material and finishing/polishing techniques. The one-step polishing system (PoGo) could be considered more effective and preferable than the other investigated finishing/polishing systems, especially for ormocer-based composite restorative material.