Objectives: The purpose of this study was to evaluate the efficacy of an experimental primer for increasing the bond strength between dentin and three different types of adhesive systems. Methods: The primer consisted of a microperoxidase (MP-11), 2-hydroxyethyl methacrylate, and water. The adhesive systems prepared were an etch-and-rinse system using a dentin conditioner containing 10wt% citric acid and 3wt% ferric chloride and 4-META/MMA-TBB resin (10-3/Super-Bond, Sun Medical), a self-etching system composed of a self-etching primer and a resin-composite luting agent (Panavia F2.0, Kuraray Medical), and a self-adhesive system composed of a resin-composite luting agent (SA Luting, Kuraray Medical). These products were used in conjunction with the MP-11 primer, and were designated as 10-3/MP-11/Super-Bond, MP-11/Panavia F2.0, and MP-11/SA Luting, respectively. The dentin surfaces of human premolar teeth were ground with #600 wet silicon carbide paper, modified with the dentin conditioners alone and also with the primer added, and then an acrylic rod was bonded to a defined bonding area (2 mm in diameter) of each specimen. Shear bond strengths were determined after 24 hours of storage in water. Data were analyzed using ANOVA and a multiple comparison test (n=9, p<0.05). Results: The highest mean bond strengths were obtained with 10-3/MP-11/Super-Bond, followed by 10-3/Super-Bond, MP-11/Panavia F2.0, MP-11/SA Luting, Panavia F2.0, and SA Luting (Table). Conclusions: It is suggested that the additional use of the MP-11 primer improved the bond strength of the etch-and-rinse, self-etching, and self-adhesive systems to dentin.
Table. Means and standard deviations of shear bond strengths (MPa).
| 10-3/Super-Bond
| Panavia F2.0
| SA Luting
|
with MP-11 | 36.3 (10.2) | 21.4 (5.6) bc
| 17.2 (3.5) ab
|
no MP-11
| 26.6 (6.7) c | 16.9 (5.7) ab
| 11.2 (5.4) a
|
Groups with identical letters indicate no significant difference (p≥0.05).