Effect of polishing systems on stain susceptibility and surface roughness of nanocomposite resin material.
BACKGROUND
Different polishing systems vary in their effect on reducing surface roughness and stain susceptibility of dental composite resin materials.


OBJECTIVE
The purpose of this study was to compare the effect of 3 polishing systems on the stain susceptibility and surface roughness of 2 nanocomposite resins and a microhybrid composite resin.


METHODS
Forty-five disks (2×10 mm) each were fabricated of 2 nanocomposite resins (Filtek Supreme XT and Tetric EvoCeram) and 1 microhybrid composite resin (Z250). Both sides of the disks were wet finished, and 1 side was polished with PoGo, Astropol, or Hi-Shine (n=5). Unpolished surfaces served as controls. The average roughness (Ra, μm) was measured with a profilometer, and the baseline color was recorded with a spectrophotometer. All specimens were incubated while soaking in a staining solution of coffee, green tea, and berry juice for 3 weeks. The color was recorded again, and the data were analyzed with 2-way ANOVA at α=.05 and Tukey multiple comparison tests.


RESULTS
All polishing systems improved the staining resistance of Filtek Supreme XT and Z250 but did not affect that of Tetric EvoCeram. The surface color of Filtek Supreme XT was changed significantly and was the smoothest after polishing with PoGo, whereas Hi-Shine produced significantly rougher surfaces but with the lowest color change. Hi-Shine produced the highest color change in Z250. The surface roughness did not differ significantly between the other polishing systems. Tetric EvoCeram showed no significant differences in color change or surface roughness.


CONCLUSIONS
Staining susceptibility and surface roughness depend mainly on material composition and on the polishing procedures. Polishing improves the staining resistance of composite resins. Nanocomposite resins did not exhibit better staining resistance or surface roughness than microhybrid composite resin.
Lecturer, Department of Restorative Dental Sciences, College of Dentistry, King Saud University, Riyadh, Saudi Arabia. Electronic address: haifabarakah343@hotmail.com.
Haifa M
HM
Barakah
Professor, Consultant, Department of Restorative Dental Sciences, College of Dentistry, King Saud University, Riyadh, Saudi Arabia.
Nadia M
NM
Taher
D000537:Aluminum Oxide / Q000737:chemistry; D001628:Beverages; D017554:Carbon Compounds, Inorganic / Q000737:chemistry; D003069:Coffee; D003116:Color; D003188:Composite Resins / Q000737:chemistry*; D003764:Dental Materials / Q000737:chemistry*; D003775:Dental Polishing / Q000295:instrumentation / Q000379:methods*; D018130:Diamond / Q000737:chemistry; D005290:Ferric Compounds / Q000737:chemistry; D005638:Fruit; D006801:Humans; D055115:Light-Curing of Dental Adhesives; D008422:Materials Testing; D053761:Nanocomposites / Q000737:chemistry*; D058105:Polymerization; D017655:Silicon Compounds / Q000737:chemistry; D013053:Spectrophotometry; D013499:Surface Properties; D013662:Tea; D013696:Temperature; D013997:Time Factors; D014025:Titanium / Q000737:chemistry; D014867:Water / Q000737:chemistry
D017554:Carbon Compounds, Inorganic; D003069:Coffee; D003188:Composite Resins; D003764:Dental Materials; D005290:Ferric Compounds; C474035:Filtek Supreme; C444701:Filtek Z250; D017655:Silicon Compounds; D013662:Tea; C501891:Tetric EvoCeram; D014867:Water; C009495:titanium dioxide; C000499:ferric oxide; D018130:Diamond; D014025:Titanium; D000537:Aluminum Oxide; C022088:silicon carbide