Water-dependent interfacial transition zone in resin-modified glass-ionomer cement/dentin interfaces

F. R. Tay, S. K. Sidhu, T. F. Watson, D. H. Pashley

Research output: Contribution to journalArticle

31 Scopus citations


The function of the interfacial transition zone (absorption layer) in resin-modified glass-ionomer cements bonded to deep dentin remains obscure. This study tested the hypotheses that the absorption layer is formed only in the presence of water derived from hydrated dentin and allows for better bonding of resin-modified glass-ionomer cements to dentin. Ten percent polyacrylic acid-conditioned, hydrated, and dehydrated deep dentin specimens were bonded with 2 resin-modified glass-ionomer cements and sealed with resins to prevent environmental water gain or loss. A non-particulate absorption layer was identified over hydrated dentin only, and was clearly discernible from the hybrid layer when bonded interfaces were examined with transmission electron microscopy. This layer was relatively more resistant to dehydration stresses, and remained intact over the dentin surface after tensile testing. The absorption layer mediates better bonding of resin-modified glass-ionomer cements to deep dentin, and functions as a stress-relieving layer to reduce stresses induced by desiccation and shrinkage.

Original languageEnglish (US)
Pages (from-to)644-649
Number of pages6
JournalJournal of Dental Research
Issue number8
Publication statusPublished - Aug 2004



  • Absorption layer
  • Hydrated dentin
  • Water movement

ASJC Scopus subject areas

  • Dentistry(all)

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