Ceramic component failure and the role of proof testing

Proof testing is an overload test used for high demand materials that must have 100% of the components tested to sort out those components with possible internal flaws. The relationship of high proof loads applied short-term, low service load, and service time of proof tested components is shown. Proof testing is now technically and clinically validated. Ceramic femoral heads that have been proof tested have been used clinically for 4 years and a significant reduction of the failure rate from 0.015% to 0.004% has resulted. However, component service life is critical and has to be protected in unison with the prosthesis manufacturer and the hospital. Because ceramics are rigid, joining of ceramic components with metals requires special attention. Specifications of the tapers and/or connection surfaces have to be appropriate to the needs of the ceramic and the manufacturer of ceramic components and the prosthesis manufacturer must adhere to strict specifications and inspection techniques. In the surgical area, training in the proper use of ceramics is a key factor to the successful performance of ceramic components.