Microtensile bond strength of eleven contemporary adhesives to dentin.
OBJECTIVE
To evaluate the microtensile bond strength (microTBS) of eleven contemporary adhesives to dentin, including three one-step self-etch systems, four two-step self-etch systems, three two-step total-etch systems, and one three-step total-etch system.


METHODS
Resin composite (Z100) was bonded to flat, mid-coronal dentin from 33 extracted human third molars using the adhesives strictly according to the respective manufacturer's instructions. After storage overnight in 37 degrees C water, the bonded specimens were sectioned into 3 to 6 slabs of approximately 1 mm thickness and 2.5 mm width. They were then trimmed into an hourglass shape resulting in an interface area of approximately 1 mm2, and subsequently subjected to microTBS testing with a crosshead speed of 1 mm/min.


RESULTS
The microTBS varied from 30.0 MPa for the one-step self-etch adhesive Prompt L-Pop 2 (ESPE) to 63.1 MPa for the three-step total-etch adhesive OptiBond FL (Kerr), the latter being the only one that significantly differed from all other microTBS values. Although not significantly different, one-step self-etch adhesives tended to have lower microTBS than two-step self-etch and two-step total-etch adhesives. Specimen failures during sample preparation occurred with Prompt L-Pop 2 (4 pretesting failures out of 17 specimens) and NRC/Prime & Bond NT (7 pretesting failures out of 14 specimens).


CONCLUSIONS
Adhesives with simplified application procedures, either following a total-etch or self-etch approach, produced lower bond strengths to dentin than a conventional three-step total-etch adhesive. Some concern exists regarding the consistency in bonding effectiveness to dentin of some self-etch adhesives.
Inoue
S
S
Department of Conservative Dentistry, School of Dentistry, Oral Pathology and Maxillofacial Surgery, Catholic University of Leuven, Kapucijnenvoer 7, 3000 Leuven, Belgium.
Vargas
M A
MA
Abe
Y
Y
Yoshida
Y
Y
Lambrechts
P
P
Vanherle
G
G
Sano
H
H
Van Meerbeek
B
B
D000134:Acid Etching, Dental; D001840:Dental Bonding; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D006801:Humans; D008422:Materials Testing; D008964:Molar, Third; D013718:Tensile Strength
D017220:Dentin-Bonding Agents