Improvement of the long-term adhesive strength between metal stem and polymethylmethacrylate bone cement by a silica/silane interlayer system

• Published in: Journal of biomedical materials research 2001-12, Vol.57 (3), p.413-418
• Main Authors: Fischer, Horst, Wirtz, Dieter C., Weber, Michael, Neuss, Michael, Niethard, Fritz U., Marx, Rudolf
• Format: Article
• Language: English
• Subjects: Adhesiveness; Alloys; Biocompatible Materials; Biological and medical sciences; Bone Cements - chemistry; long-term adhesive strength; Medical sciences; Metals - chemistry; Orthopedic surgery; Polymethyl Methacrylate - chemistry; polymethylmethacrylate; Prostheses and Implants; silane; Silanes - chemistry; silica; Silicon Dioxide - chemistry; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Tensile Strength; Time Factors; vapor deposition; Vitallium - chemistry
• ISSN: 0021-9304; 1097-4636
• DOI: 10.1002/1097-4636(20011205)57:3<413::AID-JBM1184>3.0.CO;2-R

A loss of adhesive strength between metal stem and bone cement is clinically found to be a serious problem in total hip arthroplasty and causes many operative revisions. The objective of this study was to improve the long‐term adhesive strength at this interface. A new silica/silane interlayer coating system is introduced. The layers are designed to bond the metal stem surface to the polymethylmethacrylate bone cement marginally leakage free. In vitro tensile tests were performed on specimens of TiAl6V4 and CoCrMo that were cemented by pairs with different bone cements with and without the new coating system. The specimens were stored in isotonic saline solution up to 150 days. The adhesive strength decreased about 75% within 30 days of storage on specimens of both metal alloys that were conventionally cemented without the new interlayer system. With the new coating, the high initial adhesive strength (40–50 MPa) could be stabilized for TiAl6V4 over 150 days. For the same 150‐day storage period, the adhesive strength of the coated CoCrMo alloy still decreased but the decrease was only half that experienced by the uncoated CoCrMo. The loss of adhesive strength on CoCrMo specimens could be reduced if the metal surface was activated by a plasma treatment. The new coating interface system could help to considerably reduce revision operations caused by debonding effects at the interface metal/polymethylmethacrylate bone cement. © 2001 John Wiley & Sons, Inc. J Biomed Mater Res 57: 413–418, 2001