Oral Health Is Improving But Not Equally for Everyone
A 15-Year National Study Reveals Gaps in Dental Care Among People with Chronic Diseases in Korea
Why Oral Health Matters More Than We Think
Oral health is often seen as a local issue limited to teeth and gums. In reality, it is closely connected to overall health. Poor oral health can worsen chronic non-communicable diseases (NCDs) such as diabetes, hypertension, cardiovascular disease, and even depression. Despite this strong link, people living with chronic diseases may face barriers to maintaining good oral health and accessing dental care.
A large national study from South Korea, published in PLOS One, set out to explore an important question: Do people with chronic diseases take care of their oral health as well as the general population and has this changed over time?
What Did the Researchers Study?
The researchers analyzed data from the Korea Community Health Survey, collected annually between 2008 and 2022. This survey included more than 200,000 adults each year, making it one of the most comprehensive datasets of its kind.
They compared:
The general population, and
People diagnosed with 15 different non-communicable diseases, including diabetes, hypertension, stroke, arthritis, depression, asthma, and cancer.
The study focused on two main areas:
Oral health behaviors
Toothbrushing (after meals and before bedtime)
Use of dental floss or interdental brushes
Use of oral health care services
Annual scaling (tartar removal)
Routine oral examinations
What Has Improved Over the Last 15 Years?
The good news is clear: oral health behaviors have improved steadily in Korea.
Across both the general population and people with NCDs, the study found:
More frequent toothbrushing, especially before bedtime
Increased use of preventive dental services such as scaling and oral check-ups
A general upward trend in awareness of oral hygiene over time
For example, toothbrushing before bedtime increased significantly from 2008 to 2022 in both healthy individuals and patients with diabetes or hypertension.
The Persistent Gap: Chronic Disease Patients Lag Behind
Despite overall progress, the study uncovered a consistent and concerning pattern:
people with chronic diseases still fall behind the general population in oral health care.
Key findings include:
Patients with diabetes and hypertension brushed their teeth less frequently than the general population
Use of dental floss and interdental brushes remained low among most NCD groups
Annual scaling and oral examinations were consistently less common among people with chronic diseases
In 2017, for example:
Only 36.5% of patients with diabetes had an annual oral examination
This was significantly lower than the 43.0% seen in the general population
These gaps persisted even though dental scaling and oral examinations are partially or fully covered by Korea’s national health insurance system.
Not All Patients Face the Same Challenges
The study also revealed large differences between disease groups:
Patients with stroke, arthritis, and cataracts showed particularly low use of dental services
Younger disease groups, such as those with allergic rhinitis or atopic dermatitis, generally had better oral hygiene practices
Physical limitations, reduced mobility, and difficulty with self-care likely contribute to poorer oral health among older and more vulnerable patients.
Regional Inequality Adds Another Layer
Where people live also matters.
The researchers found substantial regional disparities in oral health behaviors and dental service use:
Urban areas generally showed higher rates of scaling and oral examinations
Rural and underserved regions lagged far behind
In some provinces, the gap in annual oral examination rates exceeded 25 percentage points, highlighting inequities in access to care.
Why This Study Matters
This is one of the first long-term national studies to examine oral health behaviors across multiple chronic diseases over more than a decade. Its findings send a clear message:
Improving oral health is not just about education it requires integrated health systems that recognize oral care as part of chronic disease management.
The authors suggest practical solutions, including:
Medical dental integration, where oral health is addressed during routine chronic disease care
Targeted education for patients with NCDs and their caregivers
Stronger support for vulnerable and rural populations
Conclusion
Oral health in Korea has improved over the past 15 years but not equally for everyone. People living with chronic diseases continue to face barriers to maintaining good oral hygiene and accessing dental care, despite clear evidence that oral health plays a crucial role in managing NCDs.
Closing these gaps will require coordinated policies, integrated medical and dental services, and sustained attention to vulnerable populations. As this study shows, better oral health could be a powerful and often overlooked tool in improving long-term health outcomes for patients with chronic diseases.
Original Article Reference
Pyo J, Jeong H, Mahmudah NA, Park Y-K, Ock M.
Comparative analysis of oral health behaviour and utilisation of oral health care services in the general population and among patients with non-communicable diseases in Korea: a repeated cross-sectional survey conducted from 2008 to 2022.
PLOS One. 2025;20(4):e0321816.
DOI: 10.1371/journal.pone.0321816