Functional, Patient-Centered and Bone Remodeling Outcomes in Two Narrow-Diameter Implant Retained Mandibular Overdenture Wearers After 5 Years of Follow-Up: A Prospective Case Series.

OBJECTIVES

This prospective longitudinal case series investigated changes in functional, radiographic, and patient-centered outcomes in users of two narrow-diameter implant-retained mandibular overdentures (IMO) over a 5-year follow-up.

MATERIALS AND

METHODS

Twenty-four patients from a previous 3-year study (8 man, 16 women, 71.58 ± 7.03 years, mean mandibular edentulism duration 23.9 ± 14.4 years) were invited for a 5-year follow-up evaluation of radiographic and functional parameters. Masticatory function (MF) was assessed using the Swallowing Threshold Test (ST), with X50 and B cut-off values indicating satisfactory performance. Oral health-related quality of life (OHRQoL) was evaluated using the OHIP-Edent questionnaire. The Posterior Mandibular Area Index (PAI) was analyzed using digital panoramic radiographs. Data was analyzed using multilevel mixed-effects linear regression.

RESULTS

Twenty participants completed the 5-year follow-up evaluation. ST_X50 (4.00-3.70; p ≤ 0.01; 95% CI: 0.47-1.82) reached a significant reduction along with an increased number of masticatory cycles (59.33-65.60; p ≤ 0.01; 95% CI: 0.32-1.11) between years. The number of IMO wearers presenting satisfactory mastication increased but persisted as unsatisfactory in nine participants by year 5. Declines in the Functional Limitation and Physical Disability domains of OHRQoL were noted, with unsatisfactory mastication correlating with higher pain (coef: 2.5; p: 0.03; 95% CI: 0.25-4.74) and psychological disability scores (coef: 0.94; p ≤ 0.01; 95% CI: 0.19-1.68). PAI increased significantly (1.13-1.68; p ≤ 0.01; 95% CI: 0.24-0.56), indicating ongoing bone remodeling.

CONCLUSIONS

Although MF and bone parameters improved over 5 years, persistent unsatisfactory mastication continued to negatively affect quality of life. These findings underscore the interdependence between functional and patient-centered outcomes in IMO users.

TRIAL REGISTRATION: The Brazilian Registry of Clinical Trials (ReBEC), Trial identification: UTN code: U1111-1259-4127.