Journal of Dental Research, Vol 75, 1859-1864, Copyright © 1996 by International & American Associations for Dental Research Online Journals
Adhesive bonding to dentin with ferrous chloride primers and tri-n-butylborane-initiated luting agents
Y. Taira, H. Matsumura, K. Yoshida, T. Tanaka and M. Atsuta
Department of Fixed Prosthodontics, Nagasaki University School of Dentistry, Japan.
A variety of surface modifications with metal chlorides has been used to
enhance the bond of resins to dentin. This study investigated the
effectiveness of ferrous chloride in terms of the initiation of
polymerization in dentin bonding. The efficacy of experimental dentin
primers was evaluated via the bonding of two luting agents to dentin. The
16 primers evaluated were ferrous chloride (FeCl2) aqueous solutions, eight
with and eight without 35% 2-hydroxyethyl methacrylate (HEMA). The
concentrations of FeCl2 in the primers ranged from 2.0 x 10(-6) to 5.0 x
10(-4) mol/g. One luting agent (Super-Bond C&B) consisted of methyl
methacrylate (MMA), 4-methacryloyloxyethyl trimellitate anhydride (4-META),
and tri-n-butylborane (TBB) initiator. The other luting agent was prepared
with MMA and TBB, but without 4-META. Bovine dentin surfaces were
flattened, etched with an aqueous solution of 10% phosphoric acid, primed,
and then bonded with stainless steel rods. Tensile strengths of the bonded
specimens were measured after one-day immersion in water. Tensile testing
revealed that the bond strength was influenced by the application of FeCl2
and/or HEMA. The maximum bond strength of 33.0 MPa was recorded with the
use of primer containing FeCl2 and HEMA in MMA-TBB resin. In the case of
Super-Bond, only surface treatment of dentin with aqueous primers
containing 5.0 x 10(-5) to 2.0 x 10(-4) mol/g ferrous chloride resulted in
bond strength values above 22.0 MPa. This bonding technique, combining the
use of ferrous chloride primer with Super-Bond resin, may potentially be
applied for seating resin-bonded restorations.
