Influence of hydrostatic pulpal pressure on the microtensile bond strength of all-in-one self-etching adhesives.
OBJECTIVE
To evaluate the microtensile bond strength (microTBS) of two all-in-one self-etching adhesive systems and two self-etching adhesives with and without simulated hydrostatic pulpal pressure (PP).


METHODS
Flat coronal dentin surfaces of extracted human molars were prepared. Two all-in-one self-etching adhesive systems, One-Up Bond F (OBF; Tokuyama) and Clearfil S3 Bond (Tri-S, Kuraray Medical) and two self-etching primer adhesives, Clearfil Protect Bond (PB; Kuraray) and Clearfil SE Bond (SE; Kuraray) were applied to the dentin surfaces according to manufacturers' instructions under either a pulpal pressure (PP) of zero or 15 cm H2O. A hybrid resin composite (Clearfil AP-X, Kuraray) was used for the coronal buildup. Specimens bonded under PP were stored in water at 37 degrees C under 15 cm H2O for 24 h. Specimens not bonded under PP were stored under a PP of zero. After storage, the bonded specimens were sectioned into slabs that were trimmed to hourglass-shaped specimens, and were subjected to microtensile bond testing (microTBS). The bond strength data were statistically analyzed using two-way ANOVA and the Holm-Sidak method for multiple comparison tests (alpha = 0.05). The surface area percentage of different failure modes for each material was also statistically analyzed with three one-way ANOVAs and Tukey's multiple comparison tests.


RESULTS
The microTBS of OBF and Tri-S fell significantly under PP. However, in the, PB and SE bonded specimens under PP, there were no significant differences compared with the control groups without PP.


CONCLUSIONS
The microTBS of the two all-in-one adhesive systems decreased when PP was applied. However, the microTBS of both self-etching primer adhesives did not decrease under PP.
Hosaka
Keiichi
K
Research Associate, Cariology and Operative Dentistry, Department of Restorative Sciences, Tokyo Medical and Dental University, Tokyo, Japan. hosaka.ope@tmd.ac.jp
Nakajima
Masatoshi
M
Monticelli
Francesca
F
Carrilho
Marcela
M
Yamauti
Monica
M
Aksornmuang
Juthatip
J
Nishitani
Yoshihiro
Y
Tay
Franklin R
FR
Pashley
David H
DH
Tagami
Junji
J
D000134:Acid Etching, Dental / Q000379:methods*; D000704:Analysis of Variance; D001840:Dental Bonding; D003782:Dental Pulp / Q000502:physiology*; D003799:Dental Stress Analysis; D003804:Dentin; D017220:Dentin-Bonding Agents; D006801:Humans; D006874:Hydrostatic Pressure; D018709:Statistics, Nonparametric; D013718:Tensile Strength
D017220:Dentin-Bonding Agents