Clinical outcomes of implant-assisted removable partial dentures in patients with disabilities: a retrospective cohort study

Fixed implant prostheses are often impractical for patients with disabilities due to financial and medical limitations. Implant-assisted removable partial dentures using surveyed crowns (ICRPDs) may provide a cost-effective alternative; however, clinical outcome data in this population remain limited. Patients with disabilities treated with ICRPDs between May 2019 and June 2024 were retrospectively identified. Clinical and radiographic data were reviewed to assess implant survival, marginal bone loss (MBL), oral hygiene status, and prosthetic complications. The mean duration of available follow-up data was 33.8 months (range, 12–68 months). MBL was defined as the change between implant placement and the final recorded follow-up visit. Mixed-effects regression analysis was performed to identify factors associated with MBL. Seventeen patients received 19 ICRPDs supported by 59 implants. All 59 implants remained functional during the observed period. Mean implant-level MBL was 0.36 ± 0.53 mm. Mixed-effects regression analysis identified oral hygiene status as the only independent covariate associated with MBL: good hygiene was associated with reduced bone loss (β = − 0.56 mm, p = 0.013), whereas poor hygiene was associated with increased bone loss (β = 0.89 mm, p = 0.012). Disability type was not independently associated with MBL. Oral hygiene scores (Silness and Löe plaque index) were higher indicating worse hygiene in patients with mental disability (2.45 ± 0.51) than in those with physical disability (1.80 ± 0.66; p = 0.002), and oral hygiene correlated with MBL (r = 0.372, p = 0.010). Prosthetic complications were mainly minor mechanical events, most commonly clasp loosening (9 patients). Within the limitations of this retrospective cohort, ICRPDs demonstrated stable functional outcomes and high implant survival in patients with disabilities. Oral hygiene status was associated with peri-implant bone level changes, highlighting the importance of structured maintenance and caregiver-assisted plaque control in this population. In addition to favorable mid-term clinical outcomes, the ICRPD concept may improve treatment accessibility by reducing surgical burden and maintenance complexity in patients with disabilities who cannot realistically undergo extensive fixed implant rehabilitation.