These patients received a total of 207 NobelActive implants (Nobel Biocare, Zurich, Switzerland) placed by two experienced surgeons. Between November 2011 and February 2015, 188 implants were placed in the maxilla, and 19 implants in the mandible. All implant placement procedures were conducted at the Department of Oral and Maxillofacial Surgery of the University Medical Center, Mainz, Germany. Fifty-four implants were placed immediately after extraction, and 153 implants were placed after osseous consolidation of the extraction sockets.

Additional simultaneous bone grafting procedures, all of which were done using autologous bone, were required at 113 implant sites; another 24 sites required soft tissue augmentation with subepithelial connective tissue grafts.

Sixty-five implants were provisionalized immediately. After a healing time of at least 3 months, the final restoration was delivered. One hundred thirty implants received single-tooth restoration with a crown, 26 were loaded by an implant bridge, 19 were loaded by an implant bridge with a distal cantilever, and 32 implants were used to anchor a removable denture.

The reason for tooth removal was an endodontic failure in 38, a perio-endodontic lesion in 16, a large cyst in 11, a trauma in 24, and severe periodontitis in 56 sites. In 31 sites, a failed implant had to be removed, and in 31 sites, a pronounced bone defect was present.

The study type is a solely retrospective analysis of data obtained during follow-up in a cohort of patients treated with a CE-certified implant in a University Medical Center. Since the product is already approved in accordance with the German Medical Devices Act, additional ethics approval was not required for treatment. The study was conducted according to the principles stated in the Helsinki Declaration. Informed consent was obtained from the patient prior to any examination that was carried out for study purposes.

The cornerstones of the surgical procedure were: