Comorbidity of periodontal diseases and Alzheimer’s disease

Periodontal diseases are among the most common human ailments. At the beginning of the 21st century, the concept of “periodontal medicine” emerged, examining the relationship between periodontal pathology and other diseases of the body. Today, periodontal pathology is associated with more than 50 different systemic diseases. Alzheimer's disease is the most common form of primary degenerative dementia in late life. By 2050, the number of cases worldwide will reach 140 million. The anatomical proximity of the oral cavity and brain suggests a link between periodontal disease and CNS pathology. The authors searched the Pubmed database for sources published before October 19, 2025, that examined the relationship between periodontal pathology and Alzheimer's disease. A total of 630 publications were identified. In the present study, the authors analyzed 121 publications out of 423 sources published over the past 5 years. The data obtained during the analysis demonstrate a link between Alzheimer's disease and periodontal disease, the presence of epidemiological and genetic parallels, and pathogenetic relationships confirmed by clinical and experimental studies. Porphyromonas gingivalis , through multiple virulence factors, acts as a key pathogen in Alzheimer's disease and periodontitis. The analysis of research conducted by scientists over the past five years suggests the importance of interdisciplinary approaches in understanding the systemic consequences of periodontal disease and its potential impact on brain health. The relationship between periodontal disease and Alzheimer's disease suggests that oral health is an important factor in the prevention and treatment of Alzheimer's disease.