Shear Bond Strength Investigation of an Experimental Self-etching Bonding System

Objective: The purpose of this study was to investigate the shear bond strength of an experimental self-etching bonding system (Ivoclar Vivadent) on dentin surfaces. Methods: Human molar and premolar teeth were collected, cleaned and mounted vertically in acrylic, with the crowns exposed. The occlusal surface of each tooth was removed with an Isomet low speed saw to expose a flat dentin surface. Dentin surfaces were roughened with 320 grit Si-C paper. The teeth were randomly separated into three groups of twelve teeth each: Group A - Experimental, Group B - Clearfil SE Bond (J. Morita), Group C - Prompt L-Pop (3M ESPE). The bonding agents were placed according to manufacturer's instructions. A split mold (inner diam. 3.5 mm) was placed onto the dentin surface and composite resin (EsthetX, Dentsply Caulk, shade A3) was placed in increments and light cured to build a composite resin post onto the dentin surface. Samples were stored in distilled water for 24 hours. The samples were subjected to shear testing using an Instron Model 4202 with a crosshead speed of 0.5 mm/min. Shear bond strength was recorded in MPa. A paired samples t-test was used to determine significance between groups. Results: The mean shear bond strengths are as follows: Group A (experimental) - 16.86 ± 6.81 MPa, Group B - 13.47 ± 5.72 MPa, Group C - 5.64 ± 4.55 MPa. ANOVA showed significance between groups (p=0.0001). Paired samples t-test showed that Group A had significantly higher bond strengths than Group C (p<0.0001), and Group B had significantly higher bond strengths than Group C (p=0.0025). Groups A and B were not statistically different (p>0.05). Conclusion: The experimental self-etching bonding system compared favorably to other self-etching systems currently on the market. Supported in part by Ivoclar Vivadent.