Improvement of fibroblast adherence to titanium surface by calcium phosphate coating formed with IBAD

Coatings of hydroxyapatite (HA) and duplex phases of tricalcium phosphate/hydroxyapatite (TCP/HA) on titanium (Ti) were formed by ion beam-assisted deposition (IBAD). Human gingival fibroblasts (HGFs) attachment, spreading, extracellular matrix (ECM) production, and focal adhesion plaque formation were investigated on commercially pure titanium (cpTi), HA-coated cpTi, and porous TCP/HA-coated cpTi. After standard cell culture of HGFs on these substrates, attached cell number, cell spreading area, immunostained ECM including fibronectin (FN) and type I collage, and vinculin (presenting the formation of focal adhesion plaque) were quantified by morphometric analysis using an immunofluorescence microscope. TCP/HA and HA coatings exhibited that attached cell number and cell spreading area were higher than that of cpTi, and focal adhesion plaque formed earlier than that of uncoated substrate. The attached cell number and type I collagen formation on TCP/HA were more than that on HA. These results showed that significant improvement of soft tissue adherence to Ti surface was obtained by the porous TCP/HA coating. This indicated that this surface modification method may enhance the biological seal at the cervical level of the Ti dental implants.