Periodontitis, a common oral disease, is increasingly recognized for its potential impact on systemic health, particularly its association with heart failure (HF). HF is a complex clinical syndrome with a multifactorial pathogenesis. Emerging evidence suggests that periodontitis may influence the cardiovascular system and contribute to the onset and progression of HF through mechanisms such as systemic inflammation, microbial shifts, and immune dysregulation. However, current research still faces limitations in establishing causality and elucidating the precise underlying mechanisms. Furthermore, clinical intervention strategies require further investigation. Relevant literature was identified from PubMed, Web of Science, and Scopus using keywords related to periodontitis and heart failure, and screened for relevance to epidemiological evidence, mechanistic insights, and clinical implications. The present review aimed to summarize the mechanisms linking periodontitis and HF, analyze their shared pathophysiological basis, and discuss the potential role of periodontal treatment in improving outcomes for patients with HF. Clinically, periodontal assessment may be considered in patients with heart failure as part of multidisciplinary care, but current evidence remains insufficient to support definitive recommendations that such evaluation or treatment improves HF outcomes.