Effect of polymerization mode and time of adhesive system on microleakage in composite resin restorations.
OBJECTIVE
To quantify the microleakage on restorations carried out with a two-step etch-and-rise adhesive system and nanofilled composite resin after thermal and mechanical loading cycling.


METHODS
Ninety cavities were prepared on proximal surfaces of incisive teeth, and were randomly divided according to the photoactivation time (10, 20, or 30 s) and light-curing mode (Quartz Tungsten Halogen (QTH) lamps, 450 mW/cm(2); Light Emitting Diode (LED) second generation, 1100 mW/cm(2); or LED third generation, 700 mW/cm(2)) of an adhesive system (n = 10). Following restorative procedures and thermal and mechanical loading cycling, the samples were immersed in Methylene Blue for 2 h. The samples were ground, and the powder was prepared for analysis in an absorbance spectrophotometer. All results were statistically analyzed by anova and Tukey's test at the 5% level of significance.


RESULTS
There were no significant statistical difference in microleakage between the light-curing mode (P = 0.1212) and light-curing time (P = 0.2043).


CONCLUSIONS
Different curing modes and increasing the curing time were not factors that influenced the process of microleakage.
Department of Restorative Dentistry, Piracicaba Dental School, University of Campinas, Piracicaba, Brazil.
Giulliana P
GP
Soares
Gustavo G
GG
Silva
Glaucia M B
GM
Ambrosano
Debora A N L
DA
Lima
Giselle M
GM
Marchi
José R
JR
Lovadino
Flávio H B
FH
Aguiar
D000134:Acid Etching, Dental / Q000379:methods; D000818:Animals; D002417:Cattle; D004396:Coloring Agents; D003188:Composite Resins / Q000737:chemistry*; D055117:Curing Lights, Dental / Q000145:classification; D003737:Dental Cavity Preparation / Q000145:classification; D003738:Dental Cements / Q000737:chemistry*; D003763:Dental Leakage / Q000145:classification*; D003764:Dental Materials / Q000737:chemistry*; D003793:Dental Restoration, Permanent / Q000145:classification / Q000379:methods*; D008422:Materials Testing; D008751:Methylene Blue; D053761:Nanocomposites / Q000737:chemistry; D010756:Phosphoric Acids / Q000737:chemistry; D058105:Polymerization; D011897:Random Allocation; D013053:Spectrophotometry / Q000295:instrumentation; D013314:Stress, Mechanical; D013696:Temperature; D013997:Time Factors; D014867:Water / Q000737:chemistry
C554641:Adper single bond 2; D004396:Coloring Agents; D003188:Composite Resins; D003738:Dental Cements; D003764:Dental Materials; D010756:Phosphoric Acids; C533204:filtek Z350; D014867:Water; C030242:phosphoric acid; D008751:Methylene Blue
composite resin; dental adhesives; in vitro; microleakage; polymerization; restorations