Dentin regional bond strength of self-etch and total-etch adhesive systems.
OBJECTIVE
To evaluate the microtensile bond strength (MTBS) of self-etch (with or without H(3)PO(4)-etching) and total-etch bonding systems bonded to different regions of dentin.


METHODS
Long flat dentin cavity preparations extending from top-crown to root-apex within the same tooth were performed and bonded: using two-step (Clearfil SE Bond/SEB, Resulcin Aqua Prime/RES) and one-step (Etch & Prime 3.0/EP, One-Up Bond F/OUB, Prompt L-Pop/PLP, Solist/SOL and Futurabond/FUT) self-etch adhesives; these same adhesives were also applied following H(3)PO(4)-etching of dentin and finally two more groups were bonded with total-etch adhesives (Single Bond/SB and Prime & Bond NT/PBNT). Build-ups of resin composite were constructed incrementally to ensure sufficient bulk for the MTBS test and the different regions of dentin were identified by painting with different colours on the top of the resin composite. Specimens were sliced into beams and tested in tension. ANOVA and multiple comparisons tests were used (p<0.05).


RESULTS
Regardless of the tested dentin region, SEB attained the highest MTBS to smear layer-covered surfaces (i.e., coronal dentin: 42.7MPa), while H(3)PO(4)-etching of dentin hampered bonds (i.e., coronal dentin: 27.7MPa). When bonding with PBNT, SB, RES, EP, PLP, SOL and FUT, MTBS was similar for different dentin regions. H(3)PO(4)-etching of dentin did not alter the attained MTBS.


CONCLUSIONS
SEB yielded the highest MTBS to all regions of dentin. When bonding to parallel-cut dentin, previous H(3)PO(4)-etching of dentin did not increase MTBS and differences in bond strength among dentin regions were absent.
Proença
Jatyr P
JP
Department of Dental Materials, School of Dentistry, University of Granada, Campus Cartuja s\n, 18071 Granada, Spain.
Polido
Mário
M
Osorio
Estrella
E
Erhardt
Maria Carolina G
MC
Aguilera
Fátima S
FS
García-Godoy
Franklin
F
Osorio
Raquel
R
Toledano
Manuel
M
D000134:Acid Etching, Dental / Q000379:methods*; D001840:Dental Bonding; D003799:Dental Stress Analysis; D003804:Dentin; D017220:Dentin-Bonding Agents; D006801:Humans; D008422:Materials Testing; D008964:Molar, Third; D010756:Phosphoric Acids; D019279:Resin Cements; D013499:Surface Properties; D013718:Tensile Strength; D019237:Tooth Cervix; D019228:Tooth Crown; D014092:Tooth Root
D017220:Dentin-Bonding Agents; D010756:Phosphoric Acids; D019279:Resin Cements; C030242:phosphoric acid