There is no in vitro evidence to support the choice for nanofill or su bmi cron composites over traditional microhybrids based on better surface smoothness and /or gloss , or based upon maintenance of those superficial characteristics after surface challenges
OBJECTIVES Despite nanofill and su bmi cron composites ' aim to provide high initial polishing combined with superior smoothness and gloss retention , the question still remains whether clinicians should consider using these new material s over traditional microhybrids .
The aim of this paper was to systematic ally review the literature on how nanofills and su bmi crons react to polishing procedures and surface challenges in vitro compared with microhybrids .
The paper has also given an overview of the compositional characteristics of all resin composites and polishing systems whose performance was presented herein .
Effect of surface roughness on stain resistance of dental resin composites.
BACKGROUND Surface quality of dental restorations is one of the important factors that determine the success of the restoration . Unfortunately , exterior discoloration is still a problem for dental resin composites . PURPOSE The purpose of the study was to investigate the influential factors on stain resistance of dental resin composites . MATERIAL S AND METHODS Filtek Supreme ( nanocomposite ) , Filtek A110 ( microfilled composite ) , Filtek Z250 ( microhybrid composite ) , and Filtek P60 ( microhybrid composite ) ( all products from 3 M ESPE , St. Paul , MN , USA ) were tested . Thirty-six specimens per material were prepared and r and omly assigned to 6 groups . The specimens in 5 groups were polished against 1,000- , 1,200- , 1,500- , 2,000- , and 2,500-grit s and paper , respectively . The specimens in a sixth group were polished with 2,500-grit or 1,200-grit s and paper and used as controls . Surface roughness ( Ra ) and gloss of the specimens were measured with a profilometer and a glossmeter , respectively . Specimens were immersed in a coffee solution ( control group in distilled water ) and kept in a 37 degrees C incubator .  Color was measured by a spectrophotometer at baseline , 3 days , 7 days , and 14 days , and color change ( DeltaE*(ab ) ) was calculated . RESULTS Coffee , material , Ra , and the interaction of material x Ra had statistically significant influences on the stain resistance of the dental composites tested . For most material s in coffee solution , time squared and Ra had significant effects on the discoloration . CONCLUSIONS Coffee had a significant influence on discoloration of the dental resin composite material s tested . The different composites behaved differently in coffee solution .  Discoloration increased as Ra increased for the composites tested , except with Filtek A110 . The discoloration process was accelerated with time
There is no in vitro evidence to support the choice for nanofill or su bmi cron composites over traditional microhybrids based on better surface smoothness and /or gloss , or based upon maintenance of those superficial characteristics after surface challenges
OBJECTIVES Despite nanofill and su bmi cron composites ' aim to provide high initial polishing combined with superior smoothness and gloss retention , the question still remains whether clinicians should consider using these new material s over traditional microhybrids .
The aim of this paper was to systematic ally review the literature on how nanofills and su bmi crons react to polishing procedures and surface challenges in vitro compared with microhybrids .
The paper has also given an overview of the compositional characteristics of all resin composites and polishing systems whose performance was presented herein .