Osteoporosis and Periodontal Diseases: Exploring Shared Pathways, Bidirectional Links, and Integrated Management in a Narrative Review.

Osteoporosis and periodontal diseases are chronic conditions characterized by bone loss, affecting millions of people globally, particularly in aging populations. This narrative review synthesizes evidence of their epidemiological associations, shared pathophysiological mechanisms, diagnostic correlations, and therapeutic intersections to elucidate bidirectional relationships and inform clinical practice. A comprehensive literature search was conducted across PubMed/MEDLINE, Scopus, Web of Science, Embase, and Cochrane Library from inception to September 2025, with no date restrictions. Search terms included "osteoporosis," "bone mineral density," "postmenopausal bone loss," combined with "periodontal disease," "periodontitis," "alveolar bone loss," and "attachment loss," using Boolean operators. Medical Subject Headings and Emtree terms were applied where relevant. Additional keywords targeted mechanistic overlap, including "receptor activator of nuclear factor kappa-B ligand," "osteoprotegerin," "interleukin-6," and "tumor necrosis factor-alpha." The search prioritized epidemiological studies, systematic reviews, meta-analyses, clinical trials, and basic scientific reports. Supplementary sources included hand-searching reference lists, Google Scholar, and conference abstracts from the International Association for Dental Research, European Federation of Periodontology, and American Society for Bone and Mineral Research. Inclusion was limited to English-language peer-reviewed articles addressing epidemiological, biological, diagnostic, or therapeutic links. Non-human studies, case reports, and editorials were excluded. Two reviewers independently screened the titles and abstracts, with consensus resolving discrepancies. Evidence reveals consistent associations between low systemic bone mineral density and increased periodontal attachment loss, particularly in postmenopausal women, mediated by the receptor activator of nuclear factor kappa-B ligand/osteoprotegerin (RANKL/OPG) axis and proinflammatory cytokines. Shared risk factors such as aging, smoking, diabetes, and estrogen deficiency amplify susceptibility. Antiresorptive therapies may preserve alveolar bone, whereas periodontal treatment reduces systemic inflammation. Clinical implications include cross-screening and multidisciplinary care to mitigate the risks of fracture and tooth loss. Limitations include study heterogeneity and reliance on a cross-sectional design. Future research should prioritize longitudinal studies, biomarker development, and integrated care models to advance the precise management of these interconnected diseases.