Marginal leakage of visible light-cured composite resin restorations.

Abstract

In 1972, an ultraviolet light to polymerize a composite resin was introduced to the dental profession. The light-activated resins provided advantages to the practicing dentist. Working time was almost unlimited, curing time was short, and the set material attained its final physical properties almost immediately. With the introduction of preactivated paste systems, no mixing was necessary; hence no air was incorporated into the resin during mixing.' The introduction of ultraviolet light raised the question of the potential biologic risk associated with its clinical use. 2,3 More recently, manufacturers have marketed visible light-curing resins, apparently to minimize the potential biologic risk of the ultraviolet systems. The advantages in clinical use are essentially the same as those of the ultraviolet light-cured systems. The visible light-curing systems will polymerize both conventional and microfilled composite resins. Several studies have reported the marginal leakage of conventional and microfilled self-curing composite resins. 4-6 In addition, a study specifically dealing with the marginal leakage of an ultraviolet light-activated resin system has been published. 7 In this study, the marginal leakage of several commercially available visible lightcured composite resin materials was evaluated. MATERIAL AND METHODS The composite resins selected for study were Heliosit (Vivadent USA, Tonawanda, N.Y.) and Visio-Dispers (ESPE/Premier, Norristown, Pa.), both visible lightcured microfilled composite resins; Prisma-Fil, (L. D. Caulk Co., Milford, Del.), a small-particle conventional composite resin; and and Visar-Fil (Den-Mat, Inc., Santa Maria, Calif.), a composite resin with both conventional and microfilled particles. In addition, two chemically cured composite resins were evaluated: Profile (S. S. White Dental Products International, Philadelphia, Pa.), a small-particle conventional composite