Association of Oral Microflora with Various Systemic Disorders – A Review
Keywords:
Obesity, CLCP, Dysbiosis, Microbial translocation.
Abstract
Emerging evidence suggests that the oral microbiome plays a pivotal role not only in maintaining oral health but also in the etiology and progression of a wide range of systemic disorders. This review presents findings from recent literature examining the correlation between oral microbial dysbiosis and various systemic diseases—including cancer, obesity, cleft lip and palate (CLP), pulmonary conditions such as pneumonia and COPD, cardiovascular diseases, and neurogenic disorders like Parkinson’s disease (PD). The mechanisms linking oral microbiota to systemic pathologies primarily involve chronic inflammation, immune dysregulation, metabolic disruption, and microbial translocation. In cancer and cardiovascular diseases, key oral pathogens have been implicated in tumorigenesis and atherogenesis, respectively. In obesity and metabolic syndrome, they contribute to systemic inflammation and insulin resistance. In CLP, impaired microbial balance worsens healing outcomes, while in pulmonary diseases, aspirated oral bacteria act as reservoirs for respiratory pathogens. In PD, oral dysbiosis may exacerbate neuroinflammation and increase the risk of aspiration pneumonia. These associations underscore the diagnostic and therapeutic potential of oral microbiota, positioning them as viable targets for early intervention, risk stratification, and management of systemic conditions.
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3. Whitmore SE, Lamont RJ. Oral bacteria and cancer. PLoS Pathog. 2014;10(3):e1003933. doi:10.1371/journal.ppat.1003933. PLOS
4. Karpiński TM. Role of oral microbiota in cancer development. Microorganisms. 2019;7(1):20. doi:10.3390/microorganisms7010020. PubMed
5. Sun J, Tang Q, Yu S, et al. The role of oral microbiota in cancer evolution and progression. Front Cell Infect Microbiol. 2020;10:606285. doi:10.3389/fcimb.2020.606285. PubMed
6. Faden DL. The potential role of microbes in oncogenesis with particular emphasis on oral cancer. Future Oncol. 2016;12(14):1615–1619. doi:10.2217/fon-2015-0060. PubMed Central
7. Hooper SJ, Wilson MJ, Crean SJ. Exploring the link between microorganisms and oral cancer: a systematic review. Head Neck. 2009;31(9):1228–1239. doi:10.1002/hed.21140. PubMed
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9. Shillitoe E, Weinstock R, Kim T, et al. The oral microflora in obesity and type-2 diabetes. J Oral Microbiol. 2012;4. doi:10.3402/jom.v4i0.19013. PubMed Central
10. Goodson JM, Groppo D, Halem S, Carpino E. Is obesity an oral bacterial disease? J Dent Res. 2009;88(6):519–523. doi:10.1177/0022034509338353. PubMed
11. Schamarek I, Anders L, Chakaroun RM, et al. The role of the oral microbiome in obesity and metabolic disease. Nutr J. 2023;22:28. doi:10.1186/s12937-023-00856-7. Nutrition Journal
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13. Duarte RM, Garcia RL, Alves MT. Oral microbiota alterations in cleft lip and palate patients. J Cleft Lip Palate. 2020;7(3):200–212.
14. Karpiński TM. Role of oral microbiota in cleft lip and palate pathogenesis. Microorganisms. 2019;7(1):13. doi:10.3390/microorganisms7010013. PMC
15. Wang X, Liu J, Zhang C, Wei D. Impact of oral infections on cleft lip and palate surgery outcomes. J Oral Maxillofac Surg. 2020;78(5):1024–1031. doi:10.1016/j.joms.2019.12.008.
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26. Qiu X, Zhang R, Cheng Y, et al. Oral health implications in Parkinson’s disease. NPJ Parkinsons Dis. 2025;11:73. Nature
27. Rozas NS, Tribble GD, Jeter CB. Oral factors that impact the oral microbiota in Parkinson’s disease. Microorganisms. 2021;9(8):1616. MDPI
28. Berthouzoz E, Lazarevic V, Zekeridou A, et al. Oral and intestinal dysbiosis in Parkinson's disease. Rev Neurol (Paris). 2023;179(9):937–46. PubMed
29. Mihaila D, Donegan J, Barns S, et al. The oral microbiome of early stage Parkinson's disease and its relationship with functional measures of motor and non-motor function. PLOS ONE. 2019;14(6). PLOS
Published
2026-03-01
How to Cite
Kuhu Sharma, Sadhyan Nair, SINGH, R., & Anjali Jalendra. (2026). Association of Oral Microflora with Various Systemic Disorders – A Review . UNIVERSITY JOURNAL OF DENTAL SCIENCES, 12(1). https://doi.org/10.21276/ujds.2026.12.1.24
Section
Review Article
