Interventions for Oral Frailty and Related Oral Functional Decline in Older Adults: A Systematic Review

BACKGROUND: Oral frailty is a potentially reversible state associated with systemic frailty and adverse outcomes, but evidence on non-pharmacological programmes remains scattered. OBJECTIVE: To evaluate non-pharmacological interventions for oral frailty and related oral functional decline in older adults and to identify domain-specific patterns of effect across different intervention models. METHODS: We searched PubMed, Embase, Web of Science, Cochrane Library, CNKI, Weipu, and CBM from inception to 22 November 2025 for randomised controlled trials and quasi-experimental studies in adults aged ≥ 65 years. Owing to heterogeneity, we conducted a synthesis without meta-analysis (SWiM) using vote counting by direction of effect and rated certainty using GRADE. Interventions were classified as oral exercise alone, oral exercise plus education or self-management, or multicomponent programmes adding physical activity and/or nutrition. RESULTS: Twenty-three studies (18 randomised; 5 quasi-experimental) involving 2 412 participants were included, predominantly from East Asia. Overall, interventions tended to show favourable directions in several oral-function outcomes, with domain-specific patterns. Oral exercise alone showed the most consistent improvement direction for oral motor performance, such as tongue pressure and oral diadochokinesis. Adding education or self-management more often showed improvement directions in salivary-related outcomes and xerostomia-related symptoms. Multicomponent programmes suggested favourable directions across several dimensions, including composite oral health status, although the evidence was limited by few trials. The overall certainty of evidence ranged from very low to low, reflecting heterogeneity in intervention dose and follow-up, outcome measurement and incomplete reporting. CONCLUSIONS: Non-pharmacological interventions were generally associated with favourable directions in several oral-function outcomes related to oral frailty and related oral functional decline, with programme design corresponding to different outcome domains; however, the certainty of evidence was very low to low. Future trials should standardise core outcomes, report dose and adherence clearly, and assess longer-term effects.