Penetration of monomer systems into acrylic denture teeth used as pontics

Abstract

PURPOSE: Dissolving capability and polymerization of monomer systems are related to bonding of denture teeth and fiber-reinforced composite framework of fixed dental prostheses. We aimed with this study to analyze the dissolving depth of four different monomer systems applied during different contact times on acrylic denture teeth. METHODS AND MATERIALS: 96 specimens were divided into 3 groups according to the acrylic denture teeth used: Artic 8® (Heraeus Kultzer), GC and Vitapan® (Vita). Each group was divided into four subgroups according to the monomer system used: methylmethacrylate 99%, composite primer, a flowable composite and a light-curing dimethacrylate resin. The four monomer systems were labeled with Rhodamine B for determination of their penetration into the acrylic teeth. After exposure times of 1, 5, 15 and 60 min the monomers were light cured for 5 min, with the exception of methylmethacrylate. The specimens were cut orthogonally from gingival to occlusal in four slices (n = 8/subgroup). Depths of monomer penetration were measured by a confocal scanning light microscope. Differences in penetration were evaluated with ANOVA. RESULTS: Mean values for penetration (μm) are presented in Table 1. ANOVA (R2 = 0.699) revealed significant differences in the dissolving depths according to exposure times (p < 0.001), monomers (p < 0.001), brands (p = 0.047), and their interaction (p < 0.001). CONCLUSION: The capability of monomers to dissolve the surface of acrylic denture teeth may increase the opportunity to establish a good bond between them and their fiber-reinforced composite frameworks of fixed dental prostheses.