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Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
License evidence Interpretation limitsPooling observational associations does not resolve confounding, reverse causation, heterogeneity in diagnoses or differences in oral-health ascertainment. The synthesis does not establish a single bacterial cause of Alzheimer disease or show that periodontal treatment prevents cognitive decline.
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Verification date: 2026-10-22
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