Manual or Digitally Guided Surgical Technique for Replacing Single Tooth Edentulism by Means of Sub-crestally Placed Implants. A 3-year Parallel Randomized Clinical Study on Marginal Bone Levels Stability

Brief Summary The aim of the present prospective study was to investigate after a 2-year of follow-up any influence of the surgical technique, manual or digitally guided, on peri-implant marginal bone levels stability in implants placed 1 mm sub-crestally. Patients were treated by means of platform-switched implants provided with a 5 degrees internal conical connection and supporting single screw-retained fixed crowns. Marginal bone level (MBL) measured at prosthesis installation (t0) at 1 (t1), 2 (t2) and at 3 years of follow-up visit (t3) were considered. MBL change from t0 to t3 was investigated. The distance between the implant neck and the first radiographically detected bone to implant contact was considered to evaluate the bone loss. Two groups were considered: Test Group (GD) for implant sites treated with a digitally guided surgery procedure. Control Group (FH) for implants surgically placed without digitally guided surgery, respectively. All the procedures were performed by an experienced operator. Additionally, for both groups MBL changes were correlated to different supra-crestal soft tissue height (STH) amounts: less than 3 and ≥ 3 millimeters, respectively. Peri-implant soft tissue parameters such as probing depth (PPD), modified Sulcus Bleeding Index (mBI) and modified Plaque Index (mPI), were assessed for all the restorations included.