Michiko Sato

Designing orthopedic implant surfaces: harmonization of nanotopographical and chemical aspects

Evaluation of: Charest JL, Eliason MT, Garcia AJ, King WP, Talin AA, Simmons BA: Polymer cell culture substrates with combined nanotopographical patterns and micropatterned chemical domains. J. Vac. Sci. Technol. B 23(6), 3011–3014 (2005) [1]. This paper investigates bone-forming cell (osteoblast) responses on surfaces of a well-defined chemistry and topography. Many studies have demonstrated that nanotopography (created by nano-grains, -pores, -particles, -ridges or -valleys) stimulates more positive responses from osteoblasts compared with conventional (nanosmooth) materials. In addition, manipulating the surface chemistry of implants has been another approach to enhance implant performance. In spite of the advantages of nanotopography and chemistry, the relative influence of nanotopography versus chemistry on cell responses has not been well distinguished to date. Specifically, several studies have assessed combined variations in topography and chemistry on bone formation. However, the influence of the...

Enhanced Osteoblast Adhesion on a Novel Hydroxyapatite Coating

Plasma spray deposition of hydroxyapatite (HA) onto a titanium implant involves high temperatures that may alter HA crystallinity and induce cracks in the coating. For this reason, the objective of this study was to design a novel HA coating material and method. Titanium was coated with HA, titania, and Poly (dl-lactic-glycolic acid) (PLGA) using sol-gel processing. The biocompatibility of the HA coating in the present study was compared to that of a plasmasprayed HA coating. Results of this study showed that osteoblast adhesion was promoted more in the HA coating proposed in this study than on the plasma-sprayed HA coating. In addition, hydrothermal treatment of the coating appeared to improve the biocompatibility of the HA coating. Since osteoblast adhesion is a necessary requirement for increased bonding of an implant to juxtaposed bone, these results support that hydrothermally sol-gel processed HA may be an optimal implant coating material and method.