Design and Engineering Criteria for Titanium Devices
Pure titanium and titanium alloys are considered the best biocompatible metallic implant materials. This assessment, generally accepted as valid with respect to applications in medical technology, can be explained mainly by titanium’s surface properties r
- PDF / 4,195,464 Bytes
- 29 Pages / 439.32 x 666.12 pts Page_size
- 13 Downloads / 332 Views
Beat Gasser Robert Mathys Foundation, Bettlach, Switzerland
Introduction ................................................... Basic Mechanical Aspects . ....................................... General Considerations ........................................ Geometrical Aspects .......................................... Static Loading Aspects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Dynamic Loading Aspects ...................................... Clinical Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Processing / Treatment Related Aspects ............................ Fretting and W ear-Related Aspects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. Designing Tools ................................................ Computer Aided Design (CAD) .................................. Finite Element Analysis (FEA) .................................. Summary ..................................................... Abbreviations and Symbols ...................................... References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
D. M. Brunette et al., Titanium in Medicine © Springer-Verlag Berlin Heidelberg 2001
674 676 676 679 682 684 685
688 691 693 694 695
698 699 699
674
20 Design and Engineering Criteria
20.1 Introduction Pure titanium and titanium alloys are considered the best biocompatible metallic implant materials. This assessment, generally accepted as valid with respect to applications in medical technology, can be explained mainly by titanium's surface properties resulting from the spontaneous building up of a stable and inert oxide layer (Chaps. 5 and 6); this leads to exceptional behavior with regard to biological safety (Part IV). However, the clinical successes of temporary or permanent implants and prostheses made of titanium used in traumatology, orthopedics and dental surgery do not rely only on favorable tissue reactions and excellent corrosion resistance but also on their functional design. Thanks to its good weight-specific strength titanium is among the most interesting of construction materials, and it is also used in non-medical applications. The first priority in the design of a device is its intended function, whether the function be related to the support or replacement of parts of the locomotory system, or indeed whole organs, or instruments used for the surgical repair of tissues injured by accident or illness. The later function of a construct therefore prescribes the key aspects of the designing process, which is additionally strongly influenced by the mechanical and processing properties of the material selected. The designer has therefore to evaluate whether functional and geometrical aspects of his device can be matched with several mechanical and material properties like the static strength values, the fatigue behavior, the elastic properties, and the different steps of the manufacturing process including machining or for
Data Loading...
