Hydroxyapatite as a filler for dental composite materials: mechanical properties and in vitro bioactivity of composites

  • C. Santos
  • Z. B. Luklinska
  • R. L. Clarke
  • K. W. M. Davy


Hydroxyapatite (HAp) powder was treated with γ-methacryloxypropyltrimethoxy-silane (γ-MPS) using standard techniques in both non-polar and polar systems. Infrared spectra (DRIFT) and thermogravimetric analysis (TGA) confirmed the presence of γ-MPS on the surface of the HAp filler particles. Series of experimental composites consisting of bisphenol-a-glycidyl methacrylate (BisGMA) based resin and untreated or treated HAp filler were produced to determine the mechanical properties and in vitro bioactivity. The incorporation of HAp filler into the BisGMA base resin had an enhancing effect on the flexural strength and Young's modulus of the base resin, the latter being increased by a factor of three. The mechanical properties of the filled resin were not affected by the surface treatment of the HAp, but filler loading was found to have a significant effect on Young's modulus. Higher proportions of silane-treated HAp of smaller particle size could be incorporated in the monomer phase giving rise to composites of higher stiffness. Examination of the fracture surfaces showed that the silanized HAp particles maintained better contact with the polymer matrix. In vitro study revealed that the composites incorporating silanized HAp formed a compact and continuous calcium phosphate layer on their surface after 4 weeks immersion in a simulated body fluid (SBF). © 2001 Kluwer Academic Publishers


Hydroxyapatite Flexural Strength Calcium Phosphate Simulated Body Fluid Filler Particle 
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  1. 1.
    M. Kobayashi, T. Nakamura, J. Tamura, T. Kokubo and T. Kikutani, J. Biomed. Mater. Res. 37 (1997) 301.Google Scholar
  2. 2.
    M. Saito, A. Maruoka, T. Mori, N. Sugano and K. Hino, Biomaterials 15 (1994) 156.Google Scholar
  3. 3.
    C. I. Vallo, P. E. Montemartini, M. A. Fanovice, J. M. Porto Lopez and T. R. Cuadrado, J. Biomed. Mater. Res. 48 (1999) 150.Google Scholar
  4. 4.
    R. Labella, M. Braden and S. Deb, Biomaterials 15 (1994) 1197.Google Scholar
  5. 5.
    W. Bonfield, M. D. Grynpas, A. E. Tully, J. Bowman and J. Abram, Biomaterials 2 (1981) 185.Google Scholar
  6. 6.
    M. Wang, R. Joseph and W. Bonfield, Biomaterials 19 (1998) 2357.Google Scholar
  7. 7.
    G. Willems, P. Lambrechts, M. Braem and G. Vanherle, Quintessence Int. 24 (1993) 641.Google Scholar
  8. 8.
    K. Okada and I. Omura, US pat. 5,055,497 (1991).Google Scholar
  9. 9.
    A. M. P. Dupraz, J. R. De Wijn, S. A. T. V.D. Meer and K. De Groot, J. Biomed. Mater. Res. 30 (1996) 231.Google Scholar
  10. 10.
    C. Santos, PhD Thesis, University of Santiago de Compostela, Spain (1994).Google Scholar
  11. 11.
    T. M. Chen and G. M. Braver, J. Dent. Res. 61 (1982) 1439.Google Scholar
  12. 12.
    J. Gamble, in “Chemical Anatomy, Physiology and Pathology of Extracellular Fluid”, (Harvard University Press, Cambridge, 1967).Google Scholar
  13. 13.
    E. P. Plueddemann, in “Silane Coupling Agents”, (New York, Plenum Press, 1982) p. 111.Google Scholar
  14. 14.
    H. Ishida, in “Molecular Characterization of Composite Interfaces”, (New York, Plenum Press, 1985) p. 25.Google Scholar
  15. 15.
    R. L. Clarke, in “Polymeric Dental Materials”, (Springer-Verlag, Berlin, Heidelberg, New York, 1997) p. 84.Google Scholar
  16. 16.
    H. Kikuchi, M. Nishiyama and J. M. Antonucci, Journal of Dental Research 73 (1994) 228, Abstract 1010.Google Scholar
  17. 17.
    L. L. Hench, in “Biomaterials Science: An Introduction to Materials in Medicine”, (Academic Press, 1996) p. 73.Google Scholar
  18. 18.
    F. Miyaji, Y. Morita, T. Kokubo and T. Nakamura, J. Biomed. Mater. Res. 42 (1998) 604.Google Scholar
  19. 19.
    T. Kokubo, Y. Morita, F. Miyaji, K. Nakanishi, N. Soga and T. Nakamura, in “Bioceramics 8”, (Elsevier Science, New York, 1995) p. 213.Google Scholar

Copyright information

© Kluwer Academic Publishers 2001

Authors and Affiliations

  • C. Santos
    • 1
  • Z. B. Luklinska
    • 2
  • R. L. Clarke
    • 3
  • K. W. M. Davy
    • 3
  1. 1.St. Bartholomew's and the Royal London School of Medicine and Dentistry, Department of Biomaterials in Relation to Dentistry, Queen Mary and Westfield CollegeUniversity of LondonLondonUK
  2. 2.Materials Department/IRC in Biomedical Materials, Queen Mary and Westfield CollegeUniversity of LondonLondonUK
  3. 3.IRC in Biomedical Materials, St. Bartholomew's and the Royal London School of Medicine and Dentistry. Department of Biomaterials in Relation to Dentistry, Queen Mary and Westfield CollegeUniversity of LondonLondonUK

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