In vitro cytotoxicity and surface topography evaluation of additive manufacturing titanium implant materials
Custom-designed patient-specific implants and reconstruction plates are to date commonly manufactured using two different additive manufacturing (AM) technologies: direct metal laser sintering (DMLS) and electron beam melting (EBM). The purpose of this investigation was to characterize the surface structure and to assess the cytotoxicity of titanium alloys processed using DMLS and EBM technologies as the existing information on these issues is scarce. “Processed” and “polished” DMLS and EBM disks were assessed. Microscopic examination revealed titanium alloy particles and surface flaws on the processed materials. These surface flaws were subsequently removed by polishing. Surface roughness of EBM processed titanium was higher than that of DMLS processed. The cytotoxicity results of the DMLS and EBM discs were compared with a “gold standard” commercially available titanium mandible reconstruction plate. The mean cell viability for all discs was 82.6% (range, 77.4 to 89.7) and 83.3% for the control reconstruction plate. The DMLS and EBM manufactured titanium plates were non-cytotoxic both in “processed” and in “polished” forms.
KeywordsTitanium Alloy Test Item Additive Manufacturing Electron Beam Melting Reconstruction Plate
The authors would like to thank Tekes (the Finnish Funding Agency for Technology and Innovation, grant number 660/31/2010), Helsinki University Hospital Research Funds (grant number TYH2014234) and Sigrid Jusélius Foundation (Senior Fellowship 2013) for financing the present research. We would also like to thank M.Sc. (tech) Pekka Paavola for the photograph (Fig. 1) and Professor Markku Soimasuo for helping us to interpret the cell culture tests. The late professor Yrjö T. Konttinen is acknowledged for his contributions during the early stages of the study. This study was part of the Aalto University MedAMan research project.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no competing interest.
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