The roles of titanium surface micro/nanotopography and wettability on the differential response of human osteoblast lineage cells

• Type of Material: Article
• Authors: Rolando A. Gittens, Georgia Institute of Technology; Rene Olivares-Navarrete, Georgia Institute of Technology; Alice Cheng, Georgia Institute of Technology; David M. Anderson, Georgia Institute of Technology; Taylor McLachlan, Georgia Institute of Technology; Ingrid Stephan, University Hospital Tübingen; Jurgen Geis-Gerstorfer, University Hospital Tübingen; Kenneth H. Sandhage, Georgia Institute of Technology; Andrei G. Fedorov, Georgia Institute of Technology; Frank Rupp, University Hospital Tübingen; Barbara Boyan, Emory University; Rina Tannenbaum, University of Alabama; Zvi Schwartz, Georgia Institute of Technology
• Language: English
• Date: 2013-04-01
• Publisher: Elsevier
• Publication Version: Author Accepted Manuscript (After Peer Review)
• Copyright Statement: © 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
• License: Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.1016/j.actbio.2012.12.002
• Title of Journal or Parent Work: Acta Biomaterialia
• ISSN: 1742-7061
• Volume: 9
• Issue: 4
• Start Page: 6268
• End Page: 6277
• Grant/Funding Information: This research was supported by USPHS AR052102 and the ITI Foundation.; Partial support for the work of RAG was provided by a fellowship from the Government of Panama (IFARHU-SENACYT), as well as by the IMI Program of the National Science Foundation (ICMR Program, Award No. DMR04-09848).; Support for the work of TM, YC, DMA and AGF was provided by the U.S. Air Force Office of Scientific Research (Award No. FA9550-09-1-0162).; DMA is also supported by a PSE fellowship from the Georgia Tech Institute of Paper Science and Technology.; Support for the work of KHS was provided by the U.S. Department of Energy, Office of Basic Energy Sciences (Award No. DE-SC0002245).; The PT and SLA disks were provided by Institut Straumann AG (Basel, Switzerland).
• Keywords: STRENGTH; Engineering; INTERFACE; Bone osseointegration; Technology; implants; Commercially pure grade 2 titanium; Engineering, Biomedical; CONTACT-ANGLE; Materials Science; Nanostructures; Mesenchymal stem cell differentiation; ACID-ETCHED SURFACE; MINIATURE PIGS; BONE INTEGRATION; ROUGHNESS; HYDROPHILICITY; ENERGY; Dynamic contact angle; Materials Science, Biomaterials; IMPLANTS; Science & Technology
• Research Categories: Engineering, Biomedical

Abstract

Surface micro- and nanostructural modifications of dental and orthopedic implants have shown promising in vitro, in vivo and clinical results. Surface wettability has also been suggested to play an important role in osteoblast differentiation and osseointegration. However, the available techniques to measure surface wettability are not reliable on clinically relevant, rough surfaces. Furthermore, how the differentiation state of osteoblast lineage cells impacts their response to micro/nanostructured surfaces, and the role of wettability on this response, remain unclear. In the current study, surface wettability analyses (optical sessile drop analysis, environmental scanning electron microscopic analysis and the Wilhelmy technique) indicated hydrophobic static responses for deposited water droplets on microrough and micro/nanostructured specimens, while hydrophilic responses were observed with dynamic analyses of micro/nanostructured specimens. The maturation and local factor production of human immature osteoblast-like MG63 cells was synergistically influenced by nanostructures superimposed onto microrough titanium (Ti) surfaces. In contrast, human mesenchymal stem cells cultured on micro/nanostructured surfaces in the absence of exogenous soluble factors exhibited less robust osteoblastic differentiation and local factor production compared to cultures on unmodified microroughened Ti. Our results support previous observations using Ti6Al4V surfaces showing that recognition of surface nanostructures and subsequent cell response is dependent on the differentiation state of osteoblast lineage cells. The results also indicate that this effect may be partly modulated by surface wettability. These findings support the conclusion that the successful osseointegration of an implant depends on contributions from osteoblast lineage cells at different stages of osteoblast commitment.