Effect of light-curing method and indirect veneering materials on the Knoop hardness of a resin cement.
This study evaluated the Knoop hardness of a dual-cured resin cement (Rely-X ARC) activated solely by chemical reaction (control group) or by chemical / physical mode, light-cured through a 1.5 mm thick ceramic (HeraCeram) or composite (Artglass) disc. Light curing was carried out using conventional halogen light (XL2500) for 40 s (QTH); light emitting diodes (Ultrablue Is) for 40 s (LED); and Xenon plasma arc (Apollo 95E) for 3 s (PAC). Bovine incisors had their buccal face flattened and hybridized. On this surface a rubber mold (5 mm in diameter and 1 mm in height) was bulk filled with the resin cement. A polyester strip was seated for direct light curing or through the discs of veneering materials. After dry storage in the dark (24 h 37 degrees C), the samples (n = 5) were sectioned for hardness (KHN) measurements, taken in a microhardness tester (50 gF load 15 s). The data were statistically analyzed by ANOVA and Tukey's test (alpha = 0.05). The cement presented higher Knoop hardness values with Artglass for QTH and LED, compared to HeraCeram. The control group and the PAC/Artglass group showed lower hardness values compared to the groups light-cured with QTH and LED. PAC/HeraCeram resulted in the worst combination for cement hardness values.
Iriyama
Nelson Tetsu
NT
Department of Restorative Dentistry - Piracicaba Dental School, University of Campinas (UNICAMP), Campinas, SP, Brazil.
Tango
Rubens Nisie
RN
Manetta
Izabella Paola
IP
Sinhoreti
Mário Alexandre Coelho
MA
Sobrinho
Lourenço Correr
LC
Saavedra
Guilherme de Siqueira Ferreira Anzaloni
Gde S
D000818:Animals; D002417:Cattle; D055117:Curing Lights, Dental / Q000592:standards; D003801:Dental Veneers; D006245:Hardness Tests; D055115:Light-Curing of Dental Adhesives / Q000379:methods*; D008422:Materials Testing; D019279:Resin Cements / Q000737:chemistry / Q000528:radiation effects*; D055116:Self-Curing of Dental Resins; D013499:Surface Properties; D013997:Time Factors
C095997:DCR cement; C528569:Rely-X; D019279:Resin Cements