As a result of the introduction of oral implants, it is also possible to treat patients who have a reduced occlusal system with implant-supported fixed dental prostheses. Many publications report the successful application of implant-supported single- and multi-unit fixed dental prostheses. However, it is questionable if implants are also successful in periodontally compromised patients. With respect to implant treatment, roughly 3 categories of periodontally compromised patients can be distinguished: patients who have not been treated for periodontitis, patients who have been treated for periodontitis and have stable periodontal health, and those who have been treated but have not achieved stable periodontal health. For the first group, periodontal treatment is required. Inserting implants is only indicated in cases showing steady improvement of post- operative periodontal health. The second category has no contraindication for inserting implants. For the third group, inserting implants is contraindicated absolutely. When treatment with oral implants is indicated, meticulous aftercare and a surgical treatment which enables adequate oral hygiene self-care are strict requirements.