2.2 Surgical and prosthetic procedures

To be included in the study, participants had to have an edentulous space during at least 4 months, spanning 2–3 teeth in the posterior maxilla or mandible and presence of natural teeth, partial prosthesis and/or implants in the opposite jaw in contact with the planned bridge. Patients also had to be able to receive an 11 mm long and 4 mm wide dental implant. Furthermore, each patient had to sign an informed consent. Randomization was done at the time of surgery by opening a sealed envelope containing information if 6‐mm implants or 11‐mm implants would be used.

Implant surgery was performed under local anesthesia by a single surgeon at each center. Pre‐operatively patients were given 2 g of amoxicillin or 600 mg of clindamycin. Post‐operatively, the patients were instructed to rinse with chlorhexidine solution twice a day for 10 days. The implants were used with corresponding components and were installed according to the manufacturer's recommendations. Implant placement was performed following a one‐stage surgical procedure. Corresponding healing abutments were placed and torqued to 15 Ncm. Six weeks after surgery an acrylic screw‐retained provisional restoration was placed in occlusion. A definitive screw‐retained fixed partial prosthesis (porcelain fused to metal) was installed on abutments (Uni‐Abutment or Angled Abutment) 6 months following the installation of the provisional restoration and was torqued to 15 Ncm.