SOI Immediately vs Delayed

Whether it will not be possible to place the prosthesis because of implant failure or a prosthesis that has to be remade for any reason.

defined as implant mobility and/or any infection dictating implant removal, and/or implant fracture and/or any other mechanical complication rendering the implant unusable. The stability of each individual implant will be measured by the local blinded outcome assessors manually tightening the screws with a torque of 30 Ncm at abutment connection, immediately loading, at 1,3 and 5 years after loading for the partial fixed prostheses. Once the single crowns will be cemented, their stability will be assessed by rocking the crown with the handles of two dental instruments.

Technical (fracture of the framework and/or the veneering material, screw loosening, etc.) and/or biologic (pain, swelling, suppuration, peri-implantitis, etc.) complication will be considered.

Peri-implant marginal bone level changes will be assessed on periapical radiographs took with the paralleling technique at implant placement, at initial loading, 1,3 and 5 years after loading. Ideally digital radiographs should be taken, otherwise radiographs on conventional films will be scanned into TIFF format with a 600 dpi resolution, and stored in a personal computer. Peri-implant marginal bone levels will be measured using the Scion Image (Scion Corporation, Frederick, MD, USA) software. The software will be calibrated for every single image using the known distance of the first two consecutive threads. Measurements of the mesial and distal bone crest level adjacent to each implant will be made to the nearest 0.01 mm. Reference points for the linear measurements will be: the coronal margin of the implant collar and the most coronal point of bone-to-implant contact. Bone levels will be measured.

Patients will answer the following questions (separately for each implant):

• Are you satisfied with the function of your implant-supported prostheses? Possible answers: yes absolutely, yes partly, not sure, not really, absolutely not.
• Are you satisfied with the aesthetic outcome of your implant-supported prostheses? Possible answers: yes absolutely, yes partly, not sure, not really, absolutely not.
• Would you undergo the same therapy again? Possible answers: "yes" or "no".

ISQ was measured and recorded using the IS3 (Osstem), at implant placement, at implants exposure, at the impression time, and prosthetic loading.

The soft tissue biotype will be investigated by the same surgeon at the surgical procedures using a periodontal probe into the sulcus. Greater will be the thickness of the tissue, smaller will be transparency of the periodontal probe. The amount of keratinized tissue will be evaluated 1 year after surgical procedures using a periodontal probe. This outcome will be evaluated according to the distance from the gingival margin to the mucogingival junction

Esthetic evaluation of occlusal and vestibular pictures will take every years after definite loading was done following the pink esthetic score (PES). In brief, the PES score evaluates seven variables: mesial papilla, distal papilla, soft tissue level, soft tissue contour, alveolar process deficiencies, soft tissue color and texture. A 0-1-2 scoring system was used, 0 being the lowest and 2 being the highest value, with a maximum achievable score of 14 per dental unit.