关键词: 孟德尔随机化, 牙周炎, 因果推断, 全身疾病, 遗传学

Abstract: Mendelian randomization（MR）is an analytical approach that utilizes genetic variants as instrumental variables to assess causal relationships between exposures and outcomes. Its core principle is to leverage the random allocation of genetic variants during gamete formation，effectively mitigating confounding factors，reverse causation，and measurement errors inherent in traditional observational studies，thereby enhancing the reliability of causal inference. Periodontal disease，as a multifactorial-mediated chronic inflammatory condition，relies predominantly on epidemiological observational studies to identify risk factors（e.g.，obesity，metabolic disorders），yet such methods struggle to establish definitive causal links. Furthermore，evidence regarding the impact of periodontal disease on systemic conditions（e.g.，cardiovascular diseases，diabetes）exhibits heterogeneity，and the reproducibility of conclusions remains incompletely established. Consequently，MR provides a novel causal inference paradigm for periodontal research，demonstrating unique advantages，particularly in elucidating bidirectional associations between periodontal diseases and systemic disorders. This review summarizes the advances in MR applications in periodontology，encompassing studies on pathogenic mechanisms，risk factor analyses，and systemic implications of periodontal diseases. Nevertheless，MR findings still require validation through triangulation of multiple evidence sources（e.g.，experimental verification，prospective cohort studies）to strengthen robustness of conclusions. Future research should optimize instrumental variable selection，expand sample sizes，and integrate multi-omics data to deepen mechanistic exploration，thereby providing a theoretical foundation for precision prevention/control and interdisciplinary intervention of periodontal diseases.

Key words: Mendelian randomization, periodontitis, causal inference, systemic diseases, genetics