The effect of saliva on surface hardness and water sorption of glass–ionomers and “compomers”

  • M. Aliping-McKenzie
  • R. W. A. Linden
  • J. W. Nicholson


A study is reported in which commercial dental materials (glass–ionomers, resin-modified glass–ionomer and polyacid-modified composite resins) in the form of discs of dimensions 6 mm diameter×1 mm thickness were prepared and exposed to natural salivas (parotid and unstimulated whole), artificial saliva and water for up to 1 year. Surface hardness was measured at various time intervals, and water sorption characteristics were determined. For all types of material, storage in artificial saliva gave specimens of lowest surface hardness by amounts that were generally significant to p<0.05, whereas no differences were found between specimens stored in water or either of the natural salivas. Water sorption characteristics were found to be unaffected by the nature of the storage medium. These results contrast with some previous findings and were not expected, given the known surface reactions between salivas and glass–ionomers, or the known enzymic degradation of composite resins. They demonstrate, however, that the current widespread practise of employing pure water for storage of specimens in laboratory studies is acceptable.


Polymer Laboratory Study Pure Water Lower Surface Surface Reaction 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    A. J. Rugg-Gunn, Developmental of dental caries, in ‘Paediatric Dentistry’, edited by R. R. Welbury (Oxford University Press, Great Clarendon Street, Oxford, England, 1997) p. 97.Google Scholar
  2. 2.
    I. D. Mandel, J. Amer. Dent. Assoc. 119 (1989) 298.Google Scholar
  3. 3.
    M. P. Hector and R. W. A. Linden, ‘Reflexes of salivary sectretion, neural mechanisms of salivary gland secretion’, edited by J. R. Garrett, J. Ekstrom and L. C. Anderson (volume editors). ‘Frontiers of Oral Biology’, Basel Karger, edited by R. W. A. Linden 11(11) (1999) pp. 196-217.Google Scholar
  4. 4.
    W. M. Edgar and S. M. Higham Adv. Dent. Res. 9 (1995) 235.Google Scholar
  5. 5.
    A. Vissink, F. K. L. Spijkervert and A. V. N. Amerongen, Spec. Care in Dent. 16 (1996) 95.Google Scholar
  6. 6.
    W. F. Ganong, ‘Mouth and esophagus. Regulation of gastrointestinal function, Review of Medical Physiology’, vol. 26, 5th edn. (International edition by Lange Medical Book, 1991) pp. 454-456.Google Scholar
  7. 7.
    I. B. Larsen and E. C. Munksgaard, Scand. J. Dent. Res. 99 (1991) 254.Google Scholar
  8. 8.
    P. Mojon, R. Kaltio, D. Feduik, E. B. Hawbolt and M. Macentee, Dent. Mater. 12 (1996) 83.Google Scholar
  9. 9.
    K. Okada, S. Tosaki, K. Hirota and W. R. Hume, Dent. Mater. 17 (2001) 34.Google Scholar
  10. 10.
    M. P. Hector and R. W. A. Linden, Quart. J. Exp. Physiol. 72 (1987) 285.Google Scholar
  11. 11.
    I. H. El-Kalla and F. Garcia-Godoy, Oper. Dent. 24 (1999) 2.Google Scholar
  12. 12.
    J. W. Mclean, J. W. Nicholson and A. D. Wilson, Quint. Int. 25 (1994) 587.Google Scholar
  13. 13.
    W. Geurtsen, G. Leyhausen and F. Garcia-Godoy, Dent. Mater. 15 (1999) 196.Google Scholar
  14. 14.
    W. Kanchanavasita, H. M. Anstice and G. J. Pearson, Biomaterials 18 (1997) 343.Google Scholar
  15. 15.
    V. W. H. Leung and B. W. Darvell, J. Dent. 25 (1997) 475.Google Scholar
  16. 16.
    J. W. Nicholson, J. Mater. Sci: Mater. Med. 8 (1997) 691.Google Scholar
  17. 17.
    A. U. J. Yap, Biomaterials 17 (1996) 1897.Google Scholar

Copyright information

© Kluwer Academic Publishers 2003

Authors and Affiliations

  • M. Aliping-McKenzie
    • 1
  • R. W. A. Linden
    • 2
  • J. W. Nicholson
    • 3
  1. 1.Guy’s, King’s and St Thomas’ Dental Institute, King’s College, Guy’s HospitalLondonUK
  2. 2.School of Biomedical Sciences, King’s College LondonLondonUK
  3. 3.School of Chemical and Life SciencesUniversity of Greenwich, Chatham MaritimeChatham, KentUK

Personalised recommendations