Purpose: To compare peri-implant bone and soft-tissue levels of immediate non-occlusally loaded versus non-submerged early loaded implants in partially edentulous patients 10 years after loading. Materials and methods: Fifty-two patients were randomised in five Italian private practices: 25 in the immediately loaded group and 27 in the early loaded group. To be immediately loaded, single implants had to be inserted with a torque of at least 30 Ncm, and splinted implants with a torque of at least 20 Ncm. Immediately loaded implants were provided with non-occluding temporary restorations within 48 h. After 2 months, the provisional restorations were put in full occlusion. Implants were early loaded after 2 months. Definitive restorations were provided 8 months after implant placement. Outcome measures were prosthesis failures, implant failures and complications, recorded by non-blinded assessors, and peri-implant bone and soft-tissue levels evaluated by blinded assessors. Results: Fifty-two implants were loaded immediately and 52 early. Three patients with 8 implants dropped out from the immediate group versus two patients with 3 implants from the early loaded group; all remaining patients were followed for at least 10 years after loading. One single immediately loaded implant failed 2 months after placement. Three patients with immediately loaded implants and two with early loaded implants were affected by complications. There were no statistically significant differences for implant/prosthesis failures (Fisher's exact test: P = 0.294; difference = 4%, 95% CI: -16% to 24%) and complications between groups (Fisher's exact test: P = 0.574; difference = 4.5%, 95% CI: -12% to 21%). Both groups gradually lost peri-implant bone in a highly statistically significant way at 2, 8 and 14 months, and at 4, 5 and 10 years. After 10 years, immediately loaded patients lost an average of 1.34 mm and early loaded patients lost 1.42 mm of peri-implant marginal bone. At 10 years, there was a statistically significant recession (P < 0.001) of the vestibular soft tissues from baseline (delivery of the final restorations 8 months after implant placement) at both immediate (0.38 mm) and early (0.25 mm) loaded implants. There were no statistically significant differences in terms of peri-implant bone (difference = 0.08 mm, 95% CI: -0.49 to 0.65; P = 0.49) and soft-tissue level changes (difference = 0.07 mm, 95% CI: -0.48 to 0.62; P = 0.469) between the two groups at 10 years after loading. Conclusions: In well-maintained patients, complications are uncommon and healthy and stable peri-implant tissues can be maintained for 10 years around both immediate and early loaded implants.
Keywords: dental implants, early loading, follow-up, immediate loading, partial edentulism
Conflict-of-interest statement: This trial was independently designed and initiated by the investigators. BIOMET 3i, the manufacturer of the implants used in this investigation, provided partial economic support at a later stage, and finally ZIMMER-BIOMET partially supported the present publication, however data belonged to the authors and by no means did the sponsor interfere with the conduct of the trial or the publication of its results.
