In vitro behavior of osteoblastic cells cultured in the presence of pseudowollastonite ceramic Carlos Sarmento, 1 Zofia B. Luklinska, 2 Lindsey Brown, 3 Michel Anseau, 4 Piedad N. De Aza, 5 Salvador De Aza, 6 Francis J. Hughes, 3 Ian J. McKay 3 1 Universidade Potiguar, School of Dentistry, Natal-RN 59056-000, Brazil 2 Department of Materials, Queen Mary, University of London, Mile End, London E1 4NS, United Kingdom 3 Adult Oral Health, Institute of Dentistry, Barts and The London, Queen Mary’s School of Medicine and Dentistry, Turner Street, London E1 2AD, United Kingdom 4 Laboratoire de Resonance Magnetique Nucle ´aire, Faculte ´ de Mede ´cine et de Pharmacie, Universite ´ de Mons-Hainaut, 24 Avenue du Champ de Mars, 7000 Mons, Belgium 5 Instituto de Bioingenieria, Universidad Miguel Hernandez, Edificio Torrevaillo. Avda. Ferrocarril s/n. 03202, Elche, Alicante, Spain 6 Instituto de Cera ´mica y Vidrio, CSIC, Campus de la Universidad Auto ´noma, Cantoblanco, Camino de Valdelatas, s/n, 28049, Madrid, Spain Received 1 July 2003; revised 8 December 2003; accepted 19 January 2004 Published online 10 March 2004 in Wiley InterScience (www.interscience.wiley.com). DOI: 10.1002/jbm.a.30012 Abstract: Pseudowollastonite ceramic (psW) is a bioactive ceramic that binds to bone when implanted in vivo and may be useful for the treatment of skeletal defects. However, there have been no studies that examined the interaction between psW and osteoblastic cells in vitro. This study in- vestigated the suitability of psW as a substratum for cell attachment and the ability of the material to effect osteo- blasts at a distance from the material surface. Fetal rat cal- varial cells were plated onto the ceramic and examined by scanning electron microscopy. The findings reported show that cells attached and proliferated on the surface to the ceramic. Attachment by cells to the material can be enhanced by preincubation of psW in serum or media containing fibronectin. The adhesion of cells can be inhibited by addi- tion of GRGDS peptides suggesting that adhesion to psW is mediated by integrin binding to adsorbed proteins. To study the effects of psW at a distance, cells were cultured in the presence but not in direct contact with the material. Subse- quent changes in proliferation, alkaline phosphatase expres- sion, and bone nodule formation were assessed. Cells grown in wells containing psW demonstrated an increase in both the rate and total numbers of bone nodules formed, al- though there were no differences in proliferation or alkaline phosphatase expression. Overall, these results suggest that psW is biocompatible and osteoconductive. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res 69A: 351–358, 2004 Key words: pseudowollastonite; wollastonite; osteoblasts; biomaterials; bone regeneration; osteoinduction INTRODUCTION Understanding the mechanism by which normal bone formation is controlled is critical to the rational design of materials that will not only be biocompatible but also be able to promote bone formation. A wide range of inorganic materials has been tested for their potential usefulness in situations in which bone aug- mentation is required. A variety of material composi- tions have been shown to be bioactive and to bond to bone tissue in vivo. 1 Irrespective of the material com- position, the process of bonding to bone seems to rely on a common mechanism, namely the formation of a hydroxyapatite (HA) layer on the surface of the ma- terial to which osteoblastic cells can adhere. 2 Although the biological activity of these materials is much less than, for example, substances such as bone morpho- genetic proteins, it is becoming clear that these mate- rials can promote the differentiation of osteoblastic cells. In part, this effect may reflect the release of silicon and calcium from the material during the for- mation of the surface HA layer. 3–7 Pseudowollastonite (psW) is the high-temperature phase of CaSiO 3 and it has been demonstrated that psW forms an HA layer when exposed to biological Correspondence to: F. J. Hughes; e-mail: f.j.hughes@ qmul.ac.uk Contract grant sponsor: CAPES/CNPq, Ministry of Edu- cation of Brazil © 2004 Wiley Periodicals, Inc.