Patient-reported outcome and its association with attachment type and bone volume in mandibular implant overdenture

Objective: To determine oral health-related quality of life (OHRQoL) and denture satisfaction (DS) in patients provided with mandibular implant-supported overdentures (ISOD) retained by two different attachment types, and the association of mandibular bone volume with the change in patient-reported outcome, before and after implant treatment. Material and methods: Thirty-four patients (mean age 60.70 ± 8.7 years) received telescopic crown or locator attachments for ISOD and completed OHIP-14 (Malaysian version) and DS questionnaires, at baseline (T₀) with new conventional complete dentures (CCD) and 3 months (T₁) and 3 years (T₂) after ISOD conversion. Mandibular bone volume was calculated from cone beam computed tomography (CBCT) datasets using Mimics software. Mean changes (MC) in OHIP-14 and DS at intervals were analyzed using the Wilcoxon signed-rank test and effect size (ES). The association of bone volume, implant attachment type, and other patient variables with the change in OHIP-14 and DS were determined using multivariate linear regression analysis. Results: The MC in OHIP-14 and DS scores from T₀ to T₁ and T₂ showed significant improvement with moderate and large ES, respectively. Regression analyses for the change in OHIP-14 score from T₀ to T₂ showed significant association with implant attachment type (P = 0.043), bone volume (P = 0.004), and baseline OHIP-14 (P = 0.001), while for DS, the association was only significant with baseline DS score (P = 0.001). Conclusion: Improvement in patients' OHRQoL and satisfaction with ISOD was associated with their baseline ratings. Mandibular bone volume had a stronger association for improvement in OHRQoL compared to type of attachment.