Aging and Failure of Silicone Elastomer Prostheses

The causes of failure of mctriUofacicil prostheses may be grouped into two categories the discoloration of the prostheses over time and the degradation of static and dynamic physiccd properties of polymeric matericds [29]. 

A long-term natural aging study in different types of silicone elastomers was carried out by Oldfield and Symes 

Color instabihty of the prosthesis may be attributed to ultraviolet hght exposure, ur pollution, cosmetics and the use of strong solvents to clem the prosthesis, such as benzene and xylene [50], 

Color changes may also result from imprudent habits and practices of patients. The use of tobaccos for smoking and/ or chewing should be avoided because they are capable of staining soft, porous polymeric materials. 

The effect of nanostructured and organically-modified montmorillonite fillers on the overall behavior of reinforced systems has also been explored [54]. In order to obtain relevant data and, furthermore, to reveal possible mechanisms 

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