TY - JOUR

T1 - Manufacturing conditioned roughness and wear of biomedical oxide ceramics for all-ceramic knee implants

AU - Turger, Anke

AU - Köhler, Jens

AU - Denkena, Berend

AU - Correa, Tomas A.

AU - Becher, Christoph

AU - Hurschler, Christof

N1 - Funding information: This research was funded by the Collaborative Research Center 599 for Biomedical Technology, a Center of the German Research Foundation (DFG), within the project D4 “Ceramic Implants – Automated processing of free-form surfaces and testing of low-wear ceramic implants”. The ceramic specimens used in this work were provided by CeramTec GmbH. CeramTec was not involved in the targeting of the project nor the implementation of the experiments. The support of CeramTec is appreciated.

PY - 2013/8/29

Y1 - 2013/8/29

N2 - Background: Ceramic materials are used in a growing proportion of hip joint prostheses due to their wear resistance and biocompatibility properties. However, ceramics have not been applied successfully in total knee joint endoprostheses to date. One reason for this is that with strict surface quality requirements, there are significant challenges with regard to machining. High-toughness bioceramics can only be machined by grinding and polishing processes. The aim of this study was to develop an automated process chain for the manufacturing of an all-ceramic knee implant. Methods: A five-axis machining process was developed for all-ceramic implant components. These components were used in an investigation of the influence of surface conformity on wear behavior under simplified knee joint motion. Results: The implant components showed considerably reduced wear compared to conventional material combinations. Contact area resulting from a variety of component surface shapes, with a variety of levels of surface conformity, greatly influenced wear rate. Conclusions: It is possible to realize an all-ceramic knee endoprosthesis device, with a precise and affordable manufacturing process. The shape accuracy of the component surfaces, as specified by the design and achieved during the manufacturing process, has a substantial influence on the wear behavior of the prosthesis. This result, if corroborated by results with a greater sample size, is likely to influence the design parameters of such devices.

AB - Background: Ceramic materials are used in a growing proportion of hip joint prostheses due to their wear resistance and biocompatibility properties. However, ceramics have not been applied successfully in total knee joint endoprostheses to date. One reason for this is that with strict surface quality requirements, there are significant challenges with regard to machining. High-toughness bioceramics can only be machined by grinding and polishing processes. The aim of this study was to develop an automated process chain for the manufacturing of an all-ceramic knee implant. Methods: A five-axis machining process was developed for all-ceramic implant components. These components were used in an investigation of the influence of surface conformity on wear behavior under simplified knee joint motion. Results: The implant components showed considerably reduced wear compared to conventional material combinations. Contact area resulting from a variety of component surface shapes, with a variety of levels of surface conformity, greatly influenced wear rate. Conclusions: It is possible to realize an all-ceramic knee endoprosthesis device, with a precise and affordable manufacturing process. The shape accuracy of the component surfaces, as specified by the design and achieved during the manufacturing process, has a substantial influence on the wear behavior of the prosthesis. This result, if corroborated by results with a greater sample size, is likely to influence the design parameters of such devices.

UR - http://www.scopus.com/inward/record.url?scp=84883528009&partnerID=8YFLogxK

U2 - 10.1186/1475-925X-12-84

DO - 10.1186/1475-925X-12-84

M3 - Article

C2 - 23988155

AN - SCOPUS:84883528009

VL - 12

JO - Biomedical engineering online

JF - Biomedical engineering online

SN - 1475-925X

IS - 1

M1 - 84

ER -