Recent literature has shown that short implants have achieved growing acceptance in the field of oral implantology. Since the last years, concern has decreased about the length of endosseous implants; it should be noted that all extraoral screw implants are short implants. Nevertheless, there are local physiological and biomechanical differences regarding long-term stability.

The survival rate of short dental implants was found to increase from 80 to > 90% over time. This is also confirmed in recent studies. For short dental implants supporting single crowns and fixed bridges especially in the mandible, a 2-year success rate of 97% and a 5-year outcome of 92.2% are reported. Otherwise, the success rate of 100% in the maxilla (3-year outcome) must be critically questioned in view of our findings.

Only a few reports in the literature have addressed expandable dental implants. In 2001, Jo and co-authors reported about a 40-month prospective survival of an expandable standard-length implant (10–16 mm) for immediate loading. They found a 3-year survival rate of 96.1% in the maxilla and of 94.8% in the mandible. Huré and co-authors performed a biomechanical and histologic canine study on early loaded expandable implants of 10- and 11.5-mm lengths. Six years later (2010), in orthopaedic surgery, an expandable implant was introduced. Similar with the present study, these authors addressed implants under difficult regional bony conditions.

The purpose of our study was to evaluate the intraoperative handling, safety and feasibility of a new expandable dental implant system in a heterogeneous study cohort. We found in the present pilot study an overall 3-year implant success rate of 93.3%, which is comparable with recent literature. To the best of our knowledge (PubMed), the present clinical study is the first published investigation about the usage of an expandable short dental implant system. Therefore, directly comparable data from other clinical studies are missing.