Nutritional Outcomes of Overdentures vs. Complete Dentures in Older Edentulous Adults: A Systematic Review and Meta-Analysis.

OBJECTIVE: To investigate whether implant-supported overdentures provide nutritional advantages compared with conventional complete dentures in older edentulous adults, through a systematic review and meta-analysis. METHODS: A comprehensive search was performed in PubMed/MEDLINE, Scopus, Web of Science, Cochrane Library, EMBASE, LILACS, LIVIVO and grey literature sources. Eligible studies included completely edentulous patients aged ≥ 60 years rehabilitated with overdentures or conventional complete dentures, with nutritional intake assessed using validated methods. Data extraction and risk of bias assessments were conducted independently by calibrated reviewers. Random-effects meta-analyses were performed, and the certainty of evidence was rated using GRADE. RESULTS: Nine studies met the inclusion criteria, of which five were included in the quantitative synthesis. Overdenture users showed significantly higher vitamin B12 levels at 6-month follow-up (SMD = 0.60; 95% CI: 0.18-1.02; I2 = 54%), but no consistent differences were observed for albumin or folate. Overall certainty of the evidence was rated as moderate for vitamin B12 and albumin, and low for folate, due to methodological limitations, heterogeneity in outcome measures and small sample sizes. CONCLUSION: While overdentures improve masticatory function and may transiently enhance vitamin B12 status, the current body of evidence does not support a consistent nutritional advantage over conventional dentures. High-quality, long-term trials are needed to clarify the systemic nutritional implications of prosthetic rehabilitation in older adults.