The role of surface sealants in the roughness of composites after a simulated toothbrushing test.
OBJECTIVE
To evaluate the influence of two surface sealants (BisCover/Single Bond) and three application techniques (unsealed/conventional/co-polymerization) on the roughness of two composites (Filtek Z250/Z350) after the toothbrushing test.


METHODS
Seventy-two rectangular specimens (5 mm x10 mm x 3 mm) were fabricated and assigned into 12 groups (n=6). Each sample was subjected to three random roughness readings at baseline, after 100,000 (intermediate), and 200,000 (final) toothbrushing strokes. Roughness (R) at each stage was obtained by the arithmetic mean of the reading of each specimen. Sealant removal was qualitatively examined (optical microscope) and classified into scores (0-3). Data were analyzed by Student's paired t-test, two-way ANOVA/Tukey's test, and by Wilcoxon, Kruskal-Wallis and Miller's test (alpha=0.05).


RESULTS
Z250 groups at baseline did not differ statistically from each other. Unsealed Z350 at baseline had lower R values. All the unsealed groups presented gradual decrease in R from baseline to final brushing. From baseline to the intermediate stage, Z250 co-polymerized groups presented a significant reduction in R (score 3). Conventionally sealed groups had no significant changes in R (scores 2-0.8). From baseline to the intermediate stage, the conventionally sealed Z350 Single Bond group had an increase in R (score 1.5). In the final stage, all the conventionally sealed groups presented a reduction in R (scores 0.7-0). Co-polymerized Single Bond groups had a significant reduction in R (scores 2.5-2.7), and co-polymerized BisCover groups an increase in R (scores 2.8-3).


CONCLUSIONS
At any brushing stage, sealed composites presented superior performance when compared with unsealed composites.
Cilli
Renato
R
Department of Operative Dentistry, Endodontics and Dental Materials, Bauru Dental School, University of Sao Paulo, Al. Octavio Pinheiro Brisolla, 9-75, Bauru, Sao Paulo, Brazil.
de Mattos
Maria Cecilia Ribeiro
MC
Honorio
Heitor Marques
HM
Rios
Daniela
D
de Araujo
Paulo Amarante
PA
Prakki
Anuradha
A
D000134:Acid Etching, Dental; D000179:Acrylates / Q000737:chemistry; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry*; D003764:Dental Materials / Q000737:chemistry*; D003775:Dental Polishing; D006801:Humans; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D011108:Polymers / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry*; D013499:Surface Properties; D013696:Temperature; D013997:Time Factors; D014099:Toothbrushing / Q000295:instrumentation / Q000379:methods*; D014867:Water / Q000737:chemistry
D000179:Acrylates; C481141:BisCover; D003188:Composite Resins; D003764:Dental Materials; C444701:Filtek Z250; D011108:Polymers; D019279:Resin Cements; C533204:filtek Z350; C115612:single bond; D014867:Water; D017438:Bisphenol A-Glycidyl Methacrylate