Keratoprosthesis (KPs) are made from biomaterials which can differ significantly in their physical, chemical and biological properties. There are hydrophobic matteials as well as hydrophilic materials, each material has a limited spectra of use. An complex implantant, such as a KPs needs different surfaces to be integrated stable and for a long term without causing side reactions such as inflammation or rejection. This, there a different pre requirements to be fullfilled in order to create a long tetm stable KP. Articial hydrogels differ in many kinds from the natural hydrogel, the collagen, of the cornea.In this presentation, the fundamental mechanisms of understanding hydrogels and there limits of use as well the modification of artifical hydrogels to adopt the requirements to be be used for long-term stable KP are discussed. Furthermore it will be shown, how the perfomrkance of a KP can be predicted in vivo and the results can be used to use this expermental results and translate them into clinical application. Different kinds of KPs based an hydgrogel materials, native based and artifical materials, their limits, use andtheir performanance will be presented in order to contribute to the medical advances in corneal science.