Frailty and Oral Frailty: Conceptual Evolution, Evidence of Association and Progress in Intervention Research

With the accelerating aging of the population, frailty has become a major geriatric syndrome affecting the health outcomes of older adults. Oral frailty—an early, reversible state in which oral function progresses from relative health to functional decline—has garnered attention in the fields of geriatric dentistry and geriatrics in recent years. Existing research suggests that oral frailty is associated with adverse health outcomes such as frailty, sarcopenia, malnutrition, disability, and mortality, and may hold value for early risk identification. However, at this stage, there are no unified standards for the definitions, assessment methods, or diagnostic criteria of frailty and oral frailty. Furthermore, oral frailty and systemic frailty appear to have a multifactorial and potentially bidirectional relationship, with mechanisms involving multiple pathways such as inadequate nutritional intake, decline in oral and systemic muscle function, chronic inflammation and changes in the oral microbiome, psychosocial withdrawal, and cognitive decline. Nevertheless, current evidence remains predominantly observational, and the causal relationship between these conditions—as well as whether oral interventions can improve long-term outcomes—still requires validation. Accordingly, this narrative review synthesizes the conceptual boundaries of oral frailty and its associated conditions, summarizes existing evidence from observational and intervention studies, and explores in depth the potential mechanisms underlying their association. Further research should evaluate the clinical utility of oral frailty screening within comprehensive geriatric assessment and determine whether interventions targeting oral frailty can translate improvements in oral function into clinically meaningful systemic and patient-important outcomes.