Can Regular Dental Cleaning Help Prevent Stroke? New Evidence from a Nationwide Korean Study
A simple dental routine may offer benefits beyond oral health
Stroke remains one of the leading causes of death and long-term disability worldwide. While well-known risk factors such as high blood pressure, diabetes, and smoking have been widely studied, researchers are increasingly exploring less obvious contributors—one of them being oral health.
A new nationwide study from South Korea suggests that regular dental scaling (professional tooth cleaning) may be associated with a significantly lower risk of stroke, particularly among people with moderate to severe periodontal disease.
Why Oral Health Matters for the Brain
Periodontal disease is a chronic inflammatory condition affecting the tissues that support the teeth. Beyond tooth loss and gum damage, this long-term inflammation can spill into the bloodstream, triggering systemic effects.
Previous studies have shown that oral bacteria and inflammation may contribute to:
Damage to blood vessel walls
Atherosclerosis (plaque buildup in arteries)
Increased blood clot formation
All of these processes are closely linked to the development of stroke. However, whether treating periodontal disease—especially through routine dental scaling—can actually reduce stroke risk has remained unclear.
What Did the Researchers Do?
In this study, Kim and colleagues analyzed data from the Korean National Health Insurance Service–National Health Screening Cohort, a large database representing the general population.
The researchers followed 25,758 adults with moderate to severe periodontal disease over several years. Participants were grouped based on how often they received dental scaling:
Regular scaling
Occasional scaling
Infrequent scaling
Importantly, the analysis adjusted for many known stroke risk factors, including age, sex, income level, place of residence, hypertension, diabetes, dyslipidemia, heart disease, depression, and overall comorbidity burden.
To strengthen the reliability of their findings, the authors also performed landmark analyses, a method designed to reduce bias in long-term observational studies.
Key Findings: Fewer Strokes with More Frequent Scaling
The results were striking. Compared to patients who rarely received dental scaling, those who underwent regular dental scaling had about a 60% lower risk of stroke.
Key observations included:
Stroke incidence was lowest in the regular scaling group
The protective association remained consistent after 1-year and 2-year landmark analyses
Both ischemic and hemorrhagic strokes were less common among patients receiving regular scaling
The benefit was especially noticeable in:
Men
Adults aged 65 years and older
These groups may experience a higher inflammatory burden, making them more responsive to the systemic benefits of improved periodontal care.
How Might Dental Scaling Reduce Stroke Risk?
The authors suggest several biological explanations:
Regular scaling reduces chronic oral inflammation
Lower levels of inflammatory markers such as IL-6 and TNF-α may protect blood vessels
Reduced oral bacterial load may limit bacteremia and abnormal blood clot formation
Improved endothelial function may slow the progression of atherosclerosis
Together, these effects could help explain why maintaining periodontal health may support vascular and brain health.
What Does This Mean for Public Health?
This study adds to growing evidence that oral health is deeply connected to overall systemic health. While the researchers caution that this observational study cannot prove causality, the findings suggest that routine dental scaling may play a supportive role in stroke prevention, especially for individuals already at high risk.
Given that dental scaling is a relatively simple, low-cost preventive measure, its potential benefits could extend far beyond the dental clinic.
Conclusion
Regular dental scaling was strongly associated with a lower risk of stroke among patients with moderate to severe periodontal disease in this large national cohort. These findings highlight the importance of preventive oral care—not only for healthy teeth and gums, but possibly for protecting the brain as well.
Further studies, including randomized trials, are needed to confirm whether improving periodontal care can directly reduce stroke risk.
Original Article Reference
Kim YR, Son M, Kim SR.
Association between regular dental scaling and stroke risk in patients with periodontal diseases: evidence from a Korean nationwide database.
Epidemiology and Health. 2025;47:e2025020.