The objective of this study was to evaluate effects of Palaseal® on surface roughness of acrylic resins which
passed different polishing techniques. One hundred eighty heat-polymerized polymethymethacrylate specimens
were fabricated and finished with abrasive sandpaper. Then they were randomly equally divided into six groups. A
control group (N) was neither polished nor Palaseal® coated. The others were experimental groups as follows: No
polishing with Palaseal® coating (NC), pumice and Tripoli polishing without coating (P), pumice and Tripoli polishing
with coating (PC), silicone points polishing without coating (S), silicone points polishing with coating (SC). Changes in
surface roughness were measured with a profilometer and calculated Ra of specimens. SEM was utilized for surface
visualization and surface roughness confirmation. Two-way ANOVA and Tukey Honestly Significant Difference (HSD)
were used for statistical analysis. Group (N) had the highest mean Ra value (670.5 nm.) whereas group (PC) had the
lowest mean Ra value (241.9 nm.). Groups (N, NC) had the mean Ra value (670.5, 394.5 nm.) significantly (P<0.01) more
than groups (S, SC) (300.1, 254.9 nm.) and groups (P, PC) (283.2, 241.9 nm.) respectively. Differences of the mean
Ra values between Palaseal® uncoated groups (N, P, S) and coated groups (NC, PC, SC) were statistically significant
(P<0.01). Lastly, there was interaction between surface polishing and Palaseal® coating. Palaseal® coating on heat
polymerized acrylic resins enhanced surface smoothness of acrylic resins polished with pumice and Tripoli and
silicone points, including finished with abrasive sandpaper.