Resin bonding to primary teeth using three adhesive systems

In vitro bond strengths of three resin adhesive systems were tested using 111 primary teeth. Ninety-six flat dentin surface specimens were divided into six groups consisting of 16 primed or 16 unprimed samples for each adhesive system. The remaining 15 tooth samples were divided into three groups of five to determine each adhesive system's bond strength to primary etched enamel. Resin buttons were polymerized to all specimens with visible light, thermocycled for 2000 cycles between 5 and 55 degrees C, and shear bond strength was measured with a Instron Testing Machine (Instron Engineering Corp, Canton, MA). ANOVA and multiple comparison tests showed that Optibond Multiuse Bonding Agent had a statistically greater mean shear bond strength to primary dentin (20.5 +/- 3.5 MPa) than Prisma Universal Bond 3 Multi-purpose Bonding System (9.1 +/- 4.4 MPa), Scotchbond Multi-purpose Dental Adhesive System (7.3 +/- 3.7 MPa), and primary etched enamel (9.8 +/- 4.4 MPa) at P < 0.05. This study demonstrated that resin adhesive systems may achieve bond strengths to primary dentin comparable to those of primary enamel, and that these bonds may be as strong as bonds to permanent enamel and dentin. These adhesive systems may allow more confident esthetic restoration of primary anterior teeth.