Simple additive manufacturing of an osteoconductive ceramic using suspension melt extrusion. Issue 2 (February 2017)

• Record Type: Journal Article
• Authors: Slots, Casper; Jensen, Martin Bonde; Ditzel, Nicholas; Hedegaard, Martin A.B.; Borg, Søren Wiatr; Albrektsen, Ole; Thygesen, Torben; Kassem, Moustapha; Andersen, Morten Østergaard
• Is Part Of: Dental materials. Volume 33:Issue 2(2017)
• Page Start: 198
• Page End: 208
• Publication Date: 2017-02
• Subjects: Ceramic -- Bone implant -- Additive manufacturing -- Tricalcium phosphate -- 3D printing -- Implant; Dentistry -- Periodicals; Dental materials -- Periodicals; 617.695
• DOI: 10.1016/j.dental.2016.11.012
• Languages: English
• ISSNs: 0109-5641

Abstract

Graphical abstract: Highlights: Stearic acid/tricalcium phosphate suspensions may be 3D printed with a rapid and simple process. Sintering results in a chemically pure and mechanically strong ceramics. Mesenchymal stem cells are able to adhere and form new bone on these ceramics. Abstract: Objective: Craniofacial bone trauma is a leading reason for surgery at most hospitals. Large pieces of destroyed or resected bone are often replaced with non-resorbable and stock implants, and these are associated with a variety of problems. This paper explores the use of a novel fatty acid/calcium phosphate suspension melt for simple additive manufacturing of ceramic tricalcium phosphate implants. Methods: A wide variety of non-aqueous liquids were tested to determine the formulation of a storable 3D printable tricalcium phosphate suspension ink, and only fatty acid-based inks were found to work. A heated stearic acid-tricalcium phosphate suspension melt was then 3D printed, carbonized and sintered, yielding implants with controllable macroporosities. Their microstructure, compressive strength and chemical purity were analyzed with electron microscopy, mechanical testing and Raman spectroscopy, respectively. Mesenchymal stem cell culture was used to assess their osteoconductivity as defined by collagen deposition, alkaline phosphatase secretion and de-novo mineralization. Results: After a rapid sintering process, the implants retained their pre-sintering shape with open pores. They possessed clinically relevant mechanical strength and were chemically pure. They supported adhesion of mesenchymal stem cells, and these were able to deposit collagen onto the implants, secrete alkaline phosphatase and further mineralize the ceramic. Significance: The tricalcium phosphate/fatty acid ink described here and its 3D printing may be sufficiently simple and effective to enable rapid, on-demand and in-hospital fabrication of individualized ceramic implants that allow clinicians to use them for treatment of bone trauma.