Physical characterization of different‐roughness titanium surfaces, with and without hydroxyapatite coating, and their effect on human osteoblast‐like cells

Abstract

The aim of this study was to characterize and compare various titanium (Ti) and hydroxyapatite (HA) coatings on Ti6Al4V, in view of their application on noncemented orthopedic implants. Two innovative vacuum plasma sprayed (VPS) coatings, the first of ultrahigh rough and dense Ti (PG60, Ra=74 microm) and the second of ultrahigh rough and dense Ti coated with HA (HPG60, Ra=52 microm), have been developed, and the response of osteoblast-like cells (MG-63) seeded on these new coatings was evaluated in comparison to: a low roughness and sandblasted (Ti/SA, Ra=4 microm) Ti6Al4V surface; Ti medium (TI01, Ra=18 microm), and high (TI60, Ra=40 microm) roughness VPS coatings; and the relative Ti plus HA duplex coatings (HT01, Ra=12 microm and HT60, Ra=36 microm respectively), also obtained by VPS. PG60 coating presented no open porosity, making it dense and potentially intrinsically stronger. Cell adhesion and proliferation on PG60 was similar to those of the smoothest one (Ti/SA) and adhesion on ultrahigh roughness was lower than the medium- and high-roughness coatings, whereas cell proliferation on PG60 was lower than TI60. The HA coating determined significant increases in cell proliferation at medium and high roughness levels when compared to the relative Ti coating, but not compared to the ultrahigh one; all HA-coated surfaces showed a decrease in alkaline phosphatase activity and collagen I production. Surface morphology and the HA coating strongly affected cell behavior. However, ultrahigh values of roughness are not correctly seen by cells, and the presence of HA has no improving effects.

A Modified Surface on Titanium Deposited by a Blasting Process

“…No evidence of cytotoxicity was observed using MG63 cells on any of the samples evaluated. However, the surface coating thickness and surface roughness of the CoBlast coatings was found to be lower compared to plasma HA coating in literature (20-300 µm thickness, 3-6 µm Ra) [34] with increased cell proliferation observed on plasma HA compared to grit blasted surfaces [1].…”

“…Hydroxyapatite (HA), Ca 10 (PO 4 ) 6 (OH) 2, a proven bioceramic for coating medical device implants is widely known, not only for its biocompatible and osteoconductive properties, but also for its increased mechanical properties when applied to bio-inert metals for orthopedic use [1][2][3][4]. Implant surface modifications are often required in order to prescribe a particular surface roughness and increase surface area for osteoblast attachment, as well as to enhance the bioactive and osteoconductive properties of the underlying substrate.…”

Clinical and radiographic evaluation of NobelActiveTM dental implants

“…Rougher implant surfaces have been shown to provide greater mechanical bone anchorage, as shown through push-out, pull-out, and torque testing studies (Wennerberg et al 1996, Han et al 1998. Additionally, surface topography and roughness positively affect the healing processes by promoting favourable cellular responses by means of protein surface and cell surface interactions (Borsari et al 2005, Mustafa et al 2000. The correlation between low bone density and poor primary stability can be moderated by using a minimally rough surface implant (Tabassum et al 2009).…”

Phase Reversion‐Induced Nanograined/Ultrafine‐Grained Structures in Austenitic Stainless Steel and their Significance in Modulating Cellular Response: Biochemical and Morphological Study with Fibroblasts

“…[1][2][3] In recent years, surface modification processes such as heat treatment have been explored to induce nanostructuring on the surface and consequently promote osseointegration and modulation of cellular activity. While ultrafine structures may provide benefits of enhanced cellular attachment, stimulate metabolic activity, and upregulate protein formation, [4][5][6][7][8][9] it is, however, important that we consider both surface and bulk properties of the material that is in direct contact with the bone for long term stability and success rate of prosthetic rehabilitation.…”