Influence of dentin acid-etching and NaOCl-treatment on bond strengths of self-etch adhesives.
OBJECTIVE
To determine the microtensile bond strength (microTBS) of one- and two-step self-etch adhesives bonded to sound dentin conditioned or not with phosphoric acid (H3PO4) and sodium hypochlorite (H3PO4 + NaOCl).


METHODS
Extracted human third molars had their crowns transversally sectioned to expose flat dentin surfaces that were divided into four groups, and bonded as follow: (1) according to the manufacturers' directions, (2) acid etched with 36% H3PO4, and (3) 10% NaOCl treated for 2 minutes, after H3PO4 etching. Two two-step self-etching primers (Clearfil SE Bond/SEB and Resulcin/RE), and two one-step adhesives (One-Up Bond F/OUB and Etch & Prime 3.0/EP) were examined. Composite build-ups were constructed incrementally with Tetric Ceram. The specimens were stored in humidity for 24 hours at 37 degrees C and sectioned into beams of 1.0 mm2 cross-sectional area. Each beam was tested in tension in an Instron machine at 0.5 mm/minute, and mean microTBS data (MPa) were analyzed by 2-way ANOVA and post-hoc multiple comparisons tests (P < 0.05).


RESULTS
The two-step adhesive SEB exhibited the highest bond strength when bonded to smear layer-covered dentin, whereas RE was not affected by all dentin surface conditions. H3PO4 and H3PO4 + NaOCl pretreatments significantly increased bonding efficacy of the one-step adhesives OUB and EP, respectively.
Erhardt
Maria Carolina G
MC
Department of Dental Materials, School of Dentistry, University of Granada, Spain.
Osorio
Estrella
E
Aguilera
Fátima S
FS
Proença
Jatyr P
JP
Osorio
Raquel
R
Toledano
Manuel
M
D000134:Acid Etching, Dental / Q000379:methods*; D003188:Composite Resins / Q000737:chemistry; D001840:Dental Bonding; D003804:Dentin / Q000648:ultrastructure*; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D000431:Ethanol / Q000737:chemistry; D006801:Humans; D006813:Humidity; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D016877:Oxidants / Q000737:chemistry*; D010710:Phosphates / Q000737:chemistry; D010756:Phosphoric Acids / Q000737:chemistry*; D019279:Resin Cements / Q000737:chemistry; D016369:Smear Layer; D012973:Sodium Hypochlorite / Q000737:chemistry*; D013314:Stress, Mechanical; D013499:Surface Properties; D013696:Temperature; D013718:Tensile Strength; D013997:Time Factors
C438313:Clearfil SE Bond; D003188:Composite Resins; D017220:Dentin-Bonding Agents; C469823:Etch&Prime 3.0; D008689:Methacrylates; C446260:One-Up-Bond F; D016877:Oxidants; D010710:Phosphates; D010756:Phosphoric Acids; D019279:Resin Cements; C122122:Resulcin aquaPrime; C121818:Tetric ceram; D000431:Ethanol; D012973:Sodium Hypochlorite; C030242:phosphoric acid