In addition, Buch et al. compared the different criteria proposed for implant success with regard to their clinical value. The authors demonstrated that the proposed criteria led to very different success rates 6 years after implant insertion (75–89%) and did not allow reliable comparison of the results with each other. Thus, during control visits in our practices, only prosthetic complications, but no other factors essential on reporting implant success rates were documented. Especially in the anterior maxilla, the documentation of factors essential for a good aesthetic outcome with long-term stability would be of high importance. Another fact is that all inserted implants were intentionally included, irrespective of the indication, the augmentation materials used and irrespective of whether they were already in function or not. It would be of interest to evaluate the potential impact of different implantation and augmentation procedures on early and late implant loss as other authors could show remarkable effect on early and late implant failure.

Due to this, clear conclusions on the advantages of certain procedures, materials, healing or loading times are not possible and might be subject to further discussion. According to a retrospective 10-year observation, most implant failures occurred before loading. In most of the cases, the clinical cause was unclear, but 17.5% were due to iatrogenic conditions and only 3% could be attributed to poor bone quality and quantity. This, together with our own analysis suggests that early implant loss is related to a learning curve and the surgeons’ experience, as we have encountered that early implant loss was halved after approximately every 500 implants.

Nevertheless, our analysis indicates that under the conditions of daily practice, implants in augmented bone have survival rates that tend to be even better than implants inserted in native bone.

In this retrospective analysis, more than 10,000 implants were included followed up to 20.2 years. They were inserted in a variety of indications either with or without augmentation procedures. While it was not possible to draw clear conclusions on the superiority of a certain augmentation procedure, a graft material or a membrane as the indication for the different materials and procedures might vary; the data indicated that implant survival in augmented bone may be slightly better than in pristine bone. Further well-designed, prospective, randomised, long-term studies are needed to get greater insights into this subject.