In-vitro shear bond strength of self-etching versus traditional adhesives for orthodontic luting.
OBJECTIVE
To determine the enamel shear bond strength (SBS) of various established (Resulcin Aqua Prime & Monobond N [RA], Prompt L-Pot III [PLP]) and experimental (AC-Bond [AC], AC-Bond + Desensitizer [ACD]) self-etching adhesives in comparison to fourth (Total Etch, Primer and Bonding have separate liquids; OptiBond FL [FL]) and fifth-generation (Total Etch, Primer and Bonding "One Bottle"; Excite [EX], Gluma Comfort Bond [CB]) adhesives.


METHODS
All adhesives were applied on flattened human enamel surfaces following the manufacturers' instructions and light-cured using a quartz-tungsten-halogen curing device. 3.5 x 2.0 mm Tetric Ceram A2 composite cylinders were sheared off (Zwick Universal-testing-machine 1445, 1 mm/min) after thermocycling (5-55 degrees C, 5000x). Normal distribution was tested for all groups and analysis of variance was conducted. The t-test (5% level, Bonferroni-correction) was used for statistical analysis to evaluate intergroup differences.


RESULTS
Shear bond strength in enamel: Resulcin Aqua Prime & Monobond N: 27.0 +/- 5.8 MPa, Prompt L-Pop III: 15.9 +/- 3.4 MPa, AC-Bond: 28.1 +/- 4.4 MPa, AC-Bond + Desensitizer: 22.2 +/- 4.1 MPa, OptiBond FL: 33.2 +/- 3.2 MPa, Excite: 30.5 +/- 5.1 MPa, Gluma Comfort Bond: 30.1 +/- 3.7 MPa. OptiBond FL demonstrated significantly higher SBS (p < 0.002) in enamel than Resulcin Aqua Prime & Monobond N, AC-Bond, AC-Bond + Desensitizer and Prompt L-Pop III. Resulcin Aqua Prime & Monobond N performed significantly better than Prompt L-Pop III, but did not differ from AC-Bond or AC-Bond + Desensitizer. The SBS values of Excite and Gluma Comfort Bond were both on the same level of significance as AC-Bond and Resulcin Aqua Prime & Monobond N, but the former showed superior results to AC-Bond + Desensitizer and Prompt L-Pop III. Prompt L-Pop III yielded significantly lower SBS-values than all the other products evaluated.


CONCLUSIONS
Resulcin Aqua Prime & Monobond N and AC-Bond did not differ significantly from established 5th-generation products. Further in-vivo studies are required to investigate intra-oral stability and resistance against changing forces and force directions.
Holzmeier
Marcus
M
Department of Orthodontics, Friedrich-Alexander University, Erlangen-Nuremberg, Germany. marcus.holzmeier@kfo.imed.uni-erlangen.de
Ernst
Claus-Peter
CP
Willershausen
Brita
B
Hirschfelder
Ursula
U
D000268:Adhesiveness; D002484:Cementation / Q000379:methods*; D003738:Dental Cements / Q000737:chemistry*; D045662:Dental Etching / Q000379:methods*; D003757:Dental Implantation / Q000379:methods*; D006801:Humans; D066298:In Vitro Techniques; D008422:Materials Testing; D008963:Molar / Q000737:chemistry* / Q000502:physiology*; D016910:Orthodontic Brackets; D033081:Shear Strength; D013314:Stress, Mechanical; D013718:Tensile Strength
D003738:Dental Cements