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 possib
le internal flaws. The relationship of high proof loads applied short-term,
low service Load, and service time of proof tested components is shown. Pr
oof testing is now technically and clinically validated. Ceramic femoral he
ads 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 resu
lted. However, component service life is critical and has to be protected i
n unison with the prosthesis manufacturer and the hospital. Because ceramic
s are rigid, joining of ceramic components with metals requires special att
ention. Specifications of the tapers and/or connection surfaces have to be
appropriate to the needs of the ceramic and the manufacturer of ceramic com
ponents and the prosthesis manufacturer must adhere to strict specification
s and inspection techniques. In the surgical area, training in the proper u
se of ceramics is a key factor to the successful performance of ceramic com
ponents.