Five-year results of implants with an oxidized surface placed predominantly in soft quality bone and subjected to immediate occlusal loading

Abstract

Statement of problem: Numerous studies have demonstrated the feasibility and predictability of immediate implant loading or immediate implant restoration. However, most of these studies report primarily short-term outcomes.

Purpose: The purpose of this prospective clinical study was to document the 5-year outcome of immediate occlusally loaded implants with an oxidized, microtextured surface placed to support fixed prostheses in various regions of the jaws.

Material and methods: Thirty-eight patients received a total of 51 implant-supported fixed prostheses, 29 mandibular and 22 maxillary, the day of implant insertion. Thirty were fixed partial dentures (FPDs), 20 replaced single teeth, and 1 was a fixed mandibular complete denture. The restorations were supported by 102 slightly tapered, screw-type implants, the majority of which were placed in posterior regions (88%) and primarily in soft bone quality (76%). Patients with ongoing signs of parafunctional habits were not included. All implants were placed using conventional flap procedures. Treatment with local regenerative procedures in connection with implant placement was accepted within the study design. Resonance frequency implant stability measurements and marginal periimplant soft tissue evaluations were conducted. Radiographic examinations were performed at the time of prosthesis insertion, at 1-and 6-month follow-ups, and annually at the 1- through 5-year follow-up visits. This report presents the results after 5 years of loading, summarized with descriptive statistics.

Results: Three maxillary implants were removed, although stable, in 1 patient at the 8-week follow-up due to postoperative infection in the adjacent guided bone regeneration (GBR) area. No additional implants were lost. This resulted in a cumulative implant success rate of 97.1% after 5 years of prosthetic loading. The mean marginal bone remodeling (SD) after 5 years of function was 1.54 (0.99) mm. At the 5-year examination, absence of marginal plaque and absence of bleeding on probing was reported for 75% and 74% of the sites, respectively, and remained generally unchanged from the 1-month follow-up.

Conclusions: The 5-year follow-up data indicate that an immediate loading protocol using a slightly tapered implant design with an oxidized, microtextured surface is a successful treatment alternative in regions exhibiting soft bone quality.