SOFT TISSUE SUBSTITUTES AT IMMEDIATE POST-EXTRACTIVE IMPLANTS TO REDUCE TISSUE SHRINKAGE – 3-YEAR RESULTS FROM A RANDOMIZED CONTROLLED TRIAL

PURPOSE. The aim of this parallel randomized controlled trial (RCT) was to evaluate whether placement of a soft tissue graft substitute (STGS) could decrease peri-implant tissue shrinkage at immediate post-extractive implants. MATERIALS AND METHODS. Twenty patients with one missing tooth between two adja-cent healthy teeth in aesthetic areas and at least 4 mm of bone apically to the tooth apex were randomly allocated after tooth extraction to receive or not a subepithelial buccal STGS. Implants were inserted with a torque of at least 30 Ncm and sites were grafted with a cancellous particulate allograft. Ten patients received a buccal STGS and 10 patients did not (control group). All patients were restored with non-occluding immediate provisional screw-retained crowns, replaced after 6 months by definitive metal-ceramic crowns, and were followed to 3-year after grafting/loading. RESULTS. Three-year after loading, no drop-out, crown or implant failure or complication occurred. No statistically significant difference or trends in aesthetics (difference = 0.2, 95% CI:-0.81 to 1.21; P = 0.97), peri-implant marginal bone loss (difference = 0.14 mm; 95% CI:-0.27 to 0.57; P = 0.58) and keratinized mucosa heights (difference = 0.8 mm; 95% CI:-1.79 to 3.39; P = 0.57) between the two groups were observed. CONCLUSIONS. Acknowledging that the sample size was small, no clinical benefits could be observed using a soft tissue graft substitute at immediate post-extractive implants up to 3-year after grafting. CONFLICT OF INTEREST STATEMENT. The manufacturer (BEGO Implant Systems, Bremen, Germany) of the implants used in this investigation, partially supported this trial, however data belonged to the authors and by no means the sponsor interfered with the conduct of the trial or the publication of its results.