[Concept and testing of the Tübingen immediate implant].

This introductory communication deals with the functional-anatomical, biophysical and neurophysiological considerations which led to the construction of an aluminium oxide immediate implant from a stepped cylindrical body. This intra-osseous implant differs in essential constructional features from the implant shapes known up to now; it endeavours to make use of the architecture of the natural gingival fibre apparatus for the placing of the mucosal cuff. Its surface was maximalised towards the bone, leaving out surface structures which could produce pressure points. The enlargement of surface compared with the root of the corresponding natural tooth amounts to 65 to 100% varying according to the shape of the implant. Descriptions are given of the concept of testing experimental implants, the physical and chemical characterisation of surfaces, animal-experimental steps, clinical tests including legal problems posed and the control system created with the view to large scale clinical trials.