In vitro degradation of resin-dentin bonds analyzed by microtensile bond test, scanning and transmission electron microscopy.

Our knowledge of the mechanisms responsible for the degradation of resin-dentin bonds are poorly understood. This study investigated the degradation of resin-dentin bonds after 1 year immersion in water. Resin-dentin beams (adhesive area: 0.9mm(2)) were made by bonding using a resin adhesive, to extracted human teeth. The experimental beams were stored in water for 1 year. Beams that had been stored in water for 24h were used as controls. After water storage, the beams were subjected to microtensile bond testing. The dentin side of the fractured surface was observed using FE-SEM. Subsequently, these fractured beams were embedded in epoxy resin and examined by TEM. The bond strength of the control specimens (40.3+/-15.1MPa) decreased significantly (p<0.01) after 1 year of water exposure (13.3+/-5.6MPa). Loss of resin was observed within fractured hybrid layers in the 1 year specimens but not in the controls. Transmission electron microscopic examination revealed the presence of micromorphological alterations in the collagen fibrils after 1 year of water storage. These micromorphological changes (resin elution and alteration of the collagen fibrils) seem to be responsible for the bond degradation leading to bond strength reduction.

[1]  N. Nakabayashi,et al.  A tensile test to facilitate identification of defects in dentine bonded specimens. , 1998, Journal of dentistry.

[2]  P. Lambrechts,et al.  A TEM Study of Two Water-based Adhesive Systems Bonded to Dry and Wet Dentin , 1998, Journal of dental research.

[3]  D. Pashley,et al.  Reversal of Compromised Bonding in Bleached Enamel , 2002, Journal of dental research.

[4]  D. Pashley,et al.  Long-term durability of resin dentin interface: nanoleakage vs. microtensile bond strength. , 2002, Operative dentistry.

[5]  M. Hashimoto,et al.  The effect of hybrid layer thickness on bond strength: demineralized dentin zone of the hybrid layer. , 2000, Dental materials : official publication of the Academy of Dental Materials.

[6]  P. Spencer,et al.  Unprotected protein at the dentin-adhesive interface. , 1999, Quintessence international.

[7]  M. Burrow,et al.  The influence of storage solution on dentin bond durability of resin cement. , 2000, Dental materials : official publication of the Academy of Dental Materials.

[8]  Yong Wang,et al.  Quantifying adhesive penetration in adhesive/dentin interface using confocal Raman microspectroscopy. , 2002, Journal of biomedical materials research.

[9]  M. Hashimoto,et al.  Fractured surface characterization: wet versus dry bonding. , 2002, Dental materials : official publication of the Academy of Dental Materials.

[10]  H. Sano,et al.  Microporous dentin zone beneath resin-impregnated layer. , 1994, Operative dentistry.

[11]  D H Pashley,et al.  Two Modes of Nanoleakage Expression in Single-step Adhesives , 2002, Journal of dental research.

[12]  D. Wieliczka,et al.  Interfacial Chemistry of the Dentin/Adhesive Bond , 2000, Journal of dental research.

[13]  D. Pashley,et al.  Aggressiveness of contemporary self-etching systems. I: Depth of penetration beyond dentin smear layers. , 2001, Dental materials : official publication of the Academy of Dental Materials.

[14]  C. Dörfer,et al.  The effect of NaOCl dentin treatment on nanoleakage formation. , 2001, Journal of biomedical materials research.

[15]  M. Hashimoto,et al.  Resin-tooth adhesive interfaces after long-term function. , 2001, American journal of dentistry.

[16]  D. Pashley,et al.  Comparative SEM and TEM observations of nanoleakage within the hybrid layer. , 1995, Operative dentistry.

[17]  M. Burrow,et al.  Dentin bond durability after three years using a dentin bonding agent with and without priming. , 1996, Dental materials : official publication of the Academy of Dental Materials.

[18]  P. Spencer,et al.  Adhesive phase separation at the dentin interface under wet bonding conditions. , 2002, Journal of biomedical materials research.

[19]  N. Nakabayashi,et al.  Bonding to Intact Dentin , 1996, Journal of dental research.

[20]  D. Pashley,et al.  Mechanical disruption of dentin collagen fibrils during resin-dentin bond testing. , 2000, The journal of adhesive dentistry.

[21]  J. Eick,et al.  Effect of esterase on methacrylates and methacrylate polymers in an enzyme simulator for biodurability and biocompatibility testing. , 1994, Journal of biomedical materials research.

[22]  N. Nakabayashi,et al.  Bonding to Ground Dentin by a Phenyl-P Self -etching Primer , 1994, Journal of dental research.

[23]  M. Kaga,et al.  In vivo Degradation of Resin-Dentin Bonds in Humans Over 1 to 3 Years , 2000, Journal of dental research.

[24]  F. Tay,et al.  Over-etching effects on micro-tensile bond strength and failure patterns for two dentin bonding systems. , 2002, Journal of dentistry.

[25]  B. Causton,et al.  Changes in the dentine of human teeth following extraction and their implication for in-vitro studies of adhesion to tooth substance. , 1979, Archives of oral biology.

[26]  H. Duschner,et al.  Nanoleakage at the composite-dentin interface: a review. , 2001, American journal of dentistry.

[27]  D. Pashley,et al.  Effect of Moist vs. Dry Bonding to Normal vs. Caries-affected Dentin with Scotchbond Multi-Purpose Plus , 1999, Journal of dental research.

[28]  S. Stover,et al.  Calcium buffering is required to maintain bone stiffness in saline solution. , 1996, Journal of biomechanics.

[29]  F. Tay,et al.  Aggressiveness of contemporary self-etching adhesives. Part II: etching effects on unground enamel. , 2001, Dental materials : official publication of the Academy of Dental Materials.

[30]  M. Hashimoto,et al.  The Extent to which Resin can Infiltrate Dentin by Acetone-based Adhesives , 2002 .

[31]  J. Ferracane,et al.  Solvent Degradation and Reduced Fracture Toughness in Aged Composites , 1992, Journal of dental research.

[32]  I. B. Larsen,et al.  Effect of human saliva on surface degradation of composite resins. , 1991, Scandinavian journal of dental research.

[33]  P. Spencer,et al.  Hybridization Efficiency of the Adhesive/Dentin Interface with Wet Bonding , 2003, Journal of dental research.

[34]  M. Tyas,et al.  Nanoleakage patterns of four dentin bonding systems. , 2000, Dental materials : official publication of the Academy of Dental Materials.

[35]  M. Freund,et al.  Enzymatic degradation of BISGMA/TEGDMA-polymers causing decreased microhardness and greater wear in vitro. , 1990, Scandinavian journal of dental research.

[36]  Mehdi Balooch,et al.  Nanoindentation and storage of teeth. , 2002, Journal of biomechanics.

[37]  K. Asaoka,et al.  Duration of Dentinal Tubule Occlusion Formed by Calcium Phosphate Precipitation Method: In vitro Evaluation Using Synthetic Saliva , 1995, Journal of dental research.

[38]  Hidehiko Sano,et al.  In vivo long-term durability of the bond to dentin using two adhesive systems. , 2002, The journal of adhesive dentistry.

[39]  Hidehiko Sano,et al.  Micromorphological changes in resin-dentin bonds after 1 year of water storage. , 2002, Journal of biomedical materials research.

[40]  P. Spencer,et al.  Molecular Structure of Acid-etched Dentin Smear Layers-in situ Study , 2001, Journal of dental research.

[41]  Y. Konttinen,et al.  Multiple forms of gelatinases/type IV collagenases in saliva and gingival crevicular fluid of periodontitis patients. , 1994, Journal of clinical periodontology.

[42]  W. G. Matthews,et al.  Nanoleakage: leakage within the hybrid layer. , 1995, Operative dentistry.

[43]  J. Tagami,et al.  Long-term Durability of Dentin Bonds Made with a Self-etching Primer, in vivo , 1999, Journal of dental research.

[44]  P. Spencer,et al.  Analysis of acid-treated dentin smear debris and smear layers using confocal Raman microspectroscopy. , 2002, Journal of biomedical materials research.

[45]  N. Nakabayashi,et al.  Effect of etchant variation on wet and dry dentin bonding primed with 4-META/acetone. , 2000, Dental materials : official publication of the Academy of Dental Materials.

[46]  J. Perdigão,et al.  Effect of a sodium hypochlorite gel on dentin bonding. , 2000, Dental materials : official publication of the Academy of Dental Materials.

[47]  P. Lambrechts,et al.  A novel approach to AFM characterization of adhesive tooth-biomaterial interfaces. , 1999, Journal of biomedical materials research.

[48]  M. Hashimoto,et al.  Fractographical analysis of resin-dentin bonds. , 2001, American journal of dentistry.

[49]  E. R. Fitzgerald,et al.  Dynamic mechanical measurements during the life to death transition in animal tissues. , 1975, Biorheology.