Silicon Dissolution from Microporous Silicon Substituted Hydroxyapatite and its Effect on Osteoblast Behaviour

Abstract:

In this study silicon release from SiHA into tissue culture medium was investigated under static and semi-dynamic conditions. The effect of silicon release under semi-dynamic conditions on alkaline phosphatase activity (ALP) and collagen I (CICP) expression by osteoblast like cells (HOS TE85) was also examined. Under static conditions a low level of silicon was released within 24 hours, this initial level dropped over 3-7 days but subsequently increased again by 10-14 days. Under semi-dynamic conditions silicon was released within 24 hours and was subsequently reduced with each medium change until equilibrating at close to 0 after 10 days. ALP and CICP showed significant variation in expression between culture conditions. In direct contact with SiHA ALP peaked at day 10 and CICP was constantly elevated. Cells grown in the presence of but not on SiHA expressed progressively decreasing levels of ALP from 7-14 days, with CICP peaking at day 10. On thermanox (TMX) ALP constantly increased and CICP peaked at day 10. The results indicate that silicon leaches out of the lattice of the SiHA crystal structure but may also be reprecipitated onto the substrate. We have also demonstrated that Si influences osteoblast metabolism and differentiation whether it is available as free silicon or 'bound' in the apatite lattice.

• Periodical: Key Engineering Materials (Volumes 309-311)
• Pages: 117-120
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.309-311.117
• Online since: May 2006
• Authors: Katharina Guth, Tom Buckland, Karen A. Hing
• Keywords: Biomaterial, Bone, Dissolution, Hydroxyapatite (HAP), Osteoblast, Silicon Substituted Hydroxyapatite

References

[1] Betz RR 2003 Limitations of autograft and allograft: new synthetic solutions. Orthopedics 25(5 Supplement): S561-S570.

[2] Aoki M 1991 Science and Medical Applications of Hydroxyapatite. Takayama Press System Center Co., Inc., Tokyo.

[3] Yuan H, Kurashina K, de Bruijn JD, Li Y, de Groot K, Zhang X 1999 A preliminary study on osteoinduction of two kinds of calcium phosphate ceramics. Biomaterials 20(19): 1799-806.

DOI: 10.1016/s0142-9612(99)00075-7

[4] Carlisle EM 1972 Silicon: an essential element for the chick. Science 178(61): 619-21.

[5] Raggi MA, Sabbioni C, Mandrioli R, Zini Q, Varani G 1999 Spectrophotometric determination of silicate traces in hemodialysis solutions. J Pharm Biomed Anal 20(1-2): 335-42.

DOI: 10.1016/s0731-7085(99)00054-0

[6] Ng KW, Leong DT, Hutmacher DW 2005 The challenge to measure cell proliferation in two and three dimensions. Tissue Eng 11(1-2): 182-91.

DOI: 10.1089/ten.2005.11.182

[7] Rosa AL, Beloti MM, van Noort R 2003 Osteoblastic differentiation of cultured rat bone marrow cells on hydroxyapatite with different surface topography. Dent Mater 19(8): 768-72.

DOI: 10.1016/s0109-5641(03)00024-1

[8] Porter AE, Botelho CM, Lopes MA, Santos JD, Best SM, Bonfield W 2004 Ultrastructural comparison of dissolution and apatite precipitation on hydroxyapatite and silicon-substituted hydroxyapatite in vitro and in vivo. J Biomed Mater Res 69A(4): 670-9.

DOI: 10.1002/jbm.a.30035

[9] Kokubo T, Kushitani H, Sakka S, Kitsugi T, Yamamuro T 1990 Solutions able to reproduce in vivo surface-structure changes in bioactive glass-ceramic A-W. J Biomed Mater Res 24(6): 721734.

DOI: 10.1002/jbm.820240607

[10] Hing KA, Saeed S, Annaz B, Buckland T, Revell PA 2004 silicate substitution alters the progression of bone apposition within porous hydroxyapatite bone graft substitutes 50th annual meeting of the orthopaedic research society, San Francisco.

DOI: 10.4028/www.scientific.net/kem.254-256.273

[11] Patel N, Best SM, Bonfield W, Gibson IR, Hing KA, Damien E, Revell PA 2002 A Comparative Study on the in vivo Behaviour of Hydroxyapatite and Silicon Sybstituted Hydroxyapatite Granules. Journal of Materials Science: Materials and Medicine 13: 1199-1206.

DOI: 10.1023/a:1021114710076

[12] Nakamura T, Yamamuro T, Higashi S, Kokubo T, Itoo S 1985 A new glass-ceramic for bone replacement: evaluation of its bonding to bone tissue. J Biomed Mater Res 19(6): 685-98.

DOI: 10.1002/jbm.820190608

[13] Hench L, Paschall H 1973 Direct chemical bond of bioactive glass-ceramic materials to bone and muscle. J Biomed Mater Res. 7(3): 25-42.

DOI: 10.1002/jbm.820070304

[14] Gough JE, Clupper DC, Hench LL 2004 Osteoblast responses to tape-cast and sintered bioactive glass ceramics. J Biomed Mater Res 69A(4): 621-8.

DOI: 10.1002/jbm.a.30024

[15] Reffitt DM, Ogston N, Jugdaohsingh R, Cheung HF, Evans BA, Thompson RP, Powell JJ, Hampson GN 2003 Orthosilicic acid stimulates collagen type 1 synthesis and osteoblastic differentiation in human osteoblast-like cells in vitro. Bone 32(2): 127-35.

DOI: 10.1016/s8756-3282(02)00950-x