Short strategic implants for mandibular removable partial dentures: One-year results from a pilot randomized crossover abutment type study

Clin Oral Implants Res. 2021 Oct;32(10):1176-1189. doi: 10.1111/clr.13815. Epub 2021 Aug 25.

Abstract

Objectives: The present pilot study analyzed two abutment types (a retentive ball and a non-retentive dome) in implant-assisted removable partial dentures (IARPDs) on 6 mm short implants with respect to clinical, radiological, and patient-reported outcomes (PROs), during the first year.

Materials and methods: Two implants were placed bilaterally in mandibular molar sites, converting existing free-end removable partial dentures (RPDs) to IARPDs. Twelve subjects were randomized to initially receive either the dome (Group A, n = 6) or the ball abutment (Group B, n = 6). After eight weeks, the abutments were exchanged. After another 8 weeks, the participants were given the choice of one of the abutments. Mean values and standard deviations (SD) were calculated, and random-effect linear regression analyses were applied to analyze marginal bone level alterations and PROs (α < .05).

Results: Twelve participants were included in the study; however, one dropout occurred. Patient ratings increased significantly in both study groups. The majority of the participants (82%) ultimately chose the ball abutment. The implant survival rate was 100%, and the success rate was 90.9% twelve months after implant placement (mean peri-implant bone-loss: -1.2; SD: 0.6 mm) without a statistically significant difference between the study groups, in terms of clinical- and radiological outcomes.

Conclusion: Placing 6 mm short implants at mandibular molar sites of RPD wearers seems to be a viable treatment option, based on this investigation with a short-term follow-up. Although only minor differences between the two abutments were observed, patients seem to prefer the ball over the dome abutment.

Keywords: OHRQoL; Short implant; abutment; anchor; bone-remodeling; implant overdenture; strategic implant.

Publication types

  • Clinical Trial
  • Comparative Study

MeSH terms

  • Cross-Over Studies
  • Dental Abutments
  • Dental Implants*
  • Dental Prosthesis, Implant-Supported
  • Denture, Partial, Removable*
  • Humans
  • Pilot Projects
  • Random Allocation

Substances

  • Dental Implants