A prospective study of immediately loaded single implant-retained mandibular overdentures: Preliminary one-year results

Abstract

The cost of rehabilitation of the problematic mandibular complete denture with implant-retained overdentures or implant-supported fixed prostheses is beyond the financial scope of many compromised denture patients. Therefore, a more affordable treatment alternative is desirable. The purpose of this preliminary study was to investigate the predictability of simplifying mandibular overdenture treatment using single-stage surgery and immediate prosthetic loading of a single implant. Twenty-eight patients with a mean age of 69.8 years and problematic mandibular dentures were treated. The primary complaints among the patients referred to the clinic for treatment related to poor retention of the mandibular denture, instability, denture sores, and phonetic problems. A single implant (Branemark TiUnite Mk III) was placed into the mandibular midline, achieving primary stability. A ball attachment was placed and the retentive cap incorporated into the existing denture. The patients were recalled at 3 and 12 months. Clinical assessments, radiographs made with custom film holders, and stability measurements by both manual and resonance frequency analysis methods were recorded. All complications, failures, maintenance, and reasons for failure to follow-up were noted. Visual analogue scale questionnaires were used to record patient satisfaction. A 1-way repeated-measures ANOVA was used to determine differences between means in the following categories: general satisfaction, social life, mastication of hard food, comfort, and fit (P=.05). Three implants did not achieve sufficient primary stability to be immediately loaded and were, therefore, treated with a 2-stage delayed loading protocol. The 25 immediately loaded implants were all surviving at the 12-month recall. Patient satisfaction was high, with a significant increase in all comfort and functional parameters (P values ranged from <.001 to .07). These preliminary 1-year results indicate that immediate loading of a single oxidized surface implant used to retain a mucosa-borne overdenture is a safe, reliable, and cost-effective treatment.