Single-implant mandibular overdentures: Clinical, radiographic, and patient-reported outcomes after a 5-year follow-up

Abstract

Statement of problemPrevious studies on single-implant mandibular overdentures have reported favorable results for clinical and patient-reported outcomes. However, information from longer term clinical studies is lacking. PurposeThe purpose of this clinical study was to assess clinical, radiographic, and patient-reported outcomes of edentulous individuals rehabilitated with single-implant mandibular overdentures after a 5-year follow-up. Material and methodsA prospective clinical study was performed including completely edentulous individuals who received new conventional complete dentures and then an external hexagon implant in the mandibular midline region, followed by the incorporation of a retention system (O-ring/ball attachment; Neodent). Data collection occurred at baseline and 3, 6, 12, 24, and 60 months after implant loading. Assessed outcomes included implant stability, peri-implant soft tissue condition, peri-implant marginal bone level, satisfaction with the prostheses, and oral health–related quality of life (OHRQoL). Clinical maintenance events were also recorded. Descriptive statistics, incidence rates, Wilcoxon Signed Ranks test, and Generalized Estimating Equation regression were used for data analysis (α=.05). ResultsThirty of 34 eligible participants attended the 5-year follow-up visit, mean ±standard deviation age was 68.1 ±7.8 years, and 70% were women. The overall implant survival rate was 88.9%. After 5 years, the OHRQoL showed statistically significant improvement for all evaluation periods compared with baseline (P<.001). Regarding satisfaction with the mandibular denture, a significant increase was found between all evaluation periods compared with baseline in terms of comfort, stability, and ability to masticate (P<.001). Implant stability significantly increased (P=.003), and a mean bone loss of 1.46 mm was observed compared with baseline measures. The most frequent maintenance event was replacement of the O-ring matrix (n=80). Twenty-one midline fractures of the overdenture occurred in 14 study participants. No significant changes in peri-implant soft tissue conditions were observed. ConclusionsA single-implant mandibular overdenture effectively maintained the positive effect of the intervention on oral health–related quality of life and patient satisfaction, stable peri-implant condition, and acceptable rates of prosthetic events.