TY - JOUR
T1 - Bonding mechanism and ultrastructural interfacial analysis of a single-step adhesive to dentin
AU - Ikemura, Kunio
AU - Tay, Franklin Chi Meng
AU - Hironaka, Toshiya
AU - Endo, Takeshi
AU - Pashley, David Henry
N1 - Funding Information:
We thank Dr Hatsuo Ishida, Professor of Department of Macromolecular Science and Engineering at Case Western Reserve University, Cleveland, Ohio, USA, Dr Naota Nagai and Mr Kunihiro Shouda, both from Toray Research Center Inc., Shiga, Japan, for their help and discussion. The ultrastructural analysis of this study was supported, in part, by grant DE06427 from the NIDCR, USA. The authors are grateful to Michelle Barnes for secretarial support.
PY - 2003/12
Y1 - 2003/12
N2 - Objectives. to characterize the interaction of 4-acryloxyethyltrimellitic acid (4-AET), a key ingredient in a commercial all-in-one adhesive (Reactmer Bond) with dentin apatite, to measure the solubility of 4-AET calcium (4-AETCa), and to examine the ultrastructure of the resin-dentin interface bonded by this adhesive. Methods. solubility of synthesized 4-AETCa in several solutions was measured. Flattened bovine dentin blocks were treated with 0.1wt% NaOCl for 10 min, or 5.0wt% NaOCl for 10 min, or 30 min. Fourier transform infrared analysis using attenuated total reflection (FT-IR/ATR) was performed on these four substrates before and after treatment with a 4-AET mixture (4-AET/HEMA: 40/60wt%). Undemineralized, unstained sections of human sound dentin that were bonded with the same comonomers were examined by transmission electron microscopy (TEM). Results. the respective solubilities of the 4-AETCa in water, 2-hydroxyethyl methacrylate (HEMA; 100wt%) and HEMA/water (70/30wt%) were 0.023, 0.003 and 0.014 mol/l after 2 min. The IR analysis indicated that Ca-carboxylate (new bands: νC=O:1580 and 1413 cm-1) was formed on all dentin specimens following application of 4-AET, with or without NaOCl pretreatment. TEM showed a 1 μm thick hybrid layer with some remnant apatite crystallites that were encapsulated by a layer of less electron-dense material. Significance. the results suggest that ionized carboxyl groups in 4-AET may interact with Ca2+ from apatite crystallites within the partially demineralized hybrid layer to form an insoluble calcium salt (4-AETCa) that may aid in bonding this resin system to dentin.
AB - Objectives. to characterize the interaction of 4-acryloxyethyltrimellitic acid (4-AET), a key ingredient in a commercial all-in-one adhesive (Reactmer Bond) with dentin apatite, to measure the solubility of 4-AET calcium (4-AETCa), and to examine the ultrastructure of the resin-dentin interface bonded by this adhesive. Methods. solubility of synthesized 4-AETCa in several solutions was measured. Flattened bovine dentin blocks were treated with 0.1wt% NaOCl for 10 min, or 5.0wt% NaOCl for 10 min, or 30 min. Fourier transform infrared analysis using attenuated total reflection (FT-IR/ATR) was performed on these four substrates before and after treatment with a 4-AET mixture (4-AET/HEMA: 40/60wt%). Undemineralized, unstained sections of human sound dentin that were bonded with the same comonomers were examined by transmission electron microscopy (TEM). Results. the respective solubilities of the 4-AETCa in water, 2-hydroxyethyl methacrylate (HEMA; 100wt%) and HEMA/water (70/30wt%) were 0.023, 0.003 and 0.014 mol/l after 2 min. The IR analysis indicated that Ca-carboxylate (new bands: νC=O:1580 and 1413 cm-1) was formed on all dentin specimens following application of 4-AET, with or without NaOCl pretreatment. TEM showed a 1 μm thick hybrid layer with some remnant apatite crystallites that were encapsulated by a layer of less electron-dense material. Significance. the results suggest that ionized carboxyl groups in 4-AET may interact with Ca2+ from apatite crystallites within the partially demineralized hybrid layer to form an insoluble calcium salt (4-AETCa) that may aid in bonding this resin system to dentin.
KW - Ca-carboxylate
KW - Dentin apatite
KW - FT-IR/ATR
KW - Transmission electron microscopy
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U2 - 10.1016/S0109-5641(03)00017-4
DO - 10.1016/S0109-5641(03)00017-4
M3 - Article
C2 - 14511728
AN - SCOPUS:0141838924
SN - 0109-5641
VL - 19
SP - 707
EP - 715
JO - Dental Materials
JF - Dental Materials
IS - 8
ER -