Interaction of resin-modified glass-ionomer cements with moist dentine

J Dent. 2004 Sep;32(7):521-30. doi: 10.1016/j.jdent.2004.04.005.

Abstract

Objectives: The objective of this study was to report on a novel phenomenon that occurs when resin-modified glass-ionomer cements (RMGICs) are bonded to moist human dentine.

Methods: Dentine surfaces from extracted third molars were abraded with 180-grit SiC paper. Ten teeth were prepared for each of the two RMGICs tested (Fuji II LC, GC Corp. and Photac-Fil Quick, 3M ESPE). RMGIC buildups were made according to the manufacturers' instructions. After storage at 37 degrees C, 100% humidity for 24 h, the bonded specimens were cut occlusogingivally into 0.9 x 0.9 mm beams. Dentine surfaces bonded with the two RMGICs were examined along the fractured RMGIC/dentine interfaces. Additional beams fractured within the RMGICS and at 3 mm away from the interfaces were used as controls. The fractured beams were examined using scanning electron microscopy (SEM), field emission-environmental SEM (FE-ESEM) and transmission electron microscopy (TEM).

Results: SEM and FE-ESEM revealed numerous solid spherical bodies along the RMGIC/dentine interfaces. By contrast, no spherical bodies could be identified within the RMGIC fractured 3 mm distant from the bonded interface. TEM and energy dispersive X-ray analyses performed on carbon-coated ultrathin sections showed that these solid spherical bodies consisted of a thin aluminum and silicon-rich periphery and an amorphous hydrocarbon core within the air voids of the original resin matrix.

Conclusion: The spherical bodies probably represent a continuation of GI reaction and poly(HEMA) hydrogel formation that results from water diffusion from the underlying moist dentine. Their existence provides evidence for the permeation of water through RMGIC/dentine interfaces.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Aluminum / chemistry
  • Carbon Compounds, Inorganic / chemistry
  • Dental Bonding*
  • Dentin / ultrastructure*
  • Diffusion
  • Electron Probe Microanalysis
  • Glass Ionomer Cements / chemistry*
  • Humans
  • Hydrogel, Polyethylene Glycol Dimethacrylate / chemistry
  • Microscopy, Electron
  • Microscopy, Electron, Scanning
  • Polyamines / chemistry
  • Polyhydroxyethyl Methacrylate / analogs & derivatives*
  • Polyhydroxyethyl Methacrylate / chemistry
  • Resin Cements / chemistry*
  • Resins, Synthetic / chemistry
  • Silicon / chemistry
  • Silicon Compounds / chemistry
  • Stress, Mechanical
  • Surface Properties
  • Water / chemistry

Substances

  • Carbon Compounds, Inorganic
  • Fuji II LC cement
  • Glass Ionomer Cements
  • Photac-Fil Quick
  • Polyamines
  • Resin Cements
  • Resins, Synthetic
  • Silicon Compounds
  • poly(2-hydroxyethyl methacrylate)-polyamine graft copolymer
  • Water
  • Polyhydroxyethyl Methacrylate
  • Hydrogel, Polyethylene Glycol Dimethacrylate
  • Aluminum
  • silicon carbide
  • Silicon