Smoking Leaves Its Mark on the Gums: New Study Reveals How Periodontitis Tissues Change
A closer look at what happens beneath the surface in smokers vs. non-smokers
A new study published in BMC Oral Health (2025) provides one of the most detailed snapshots to date of how cigarette smoking alters the microscopic structure of the gums—particularly in people living with Stage II Grade B periodontitis. While smoking is already known to worsen gum disease, this research zooms in on what actually happens at the tissue level, offering insights that could shape future periodontal treatment strategies.
Why This Matters
Periodontitis is a chronic inflammatory disease that damages the tissues supporting the teeth. Smoking is a well-established risk factor—not only increasing disease severity but also masking visible signs of inflammation, making gum disease harder to detect early.
But how exactly smoking alters the gums on a cellular and vascular level has remained less clear. This new study helps fill that gap.
What the Researchers Did
The research team analyzed 60 gingival tissue samples from adults undergoing periodontal surgery:
30 smokers
30 non-smokers
All participants had the same stage and grade of periodontitis, helping the researchers isolate the impact of smoking itself.
Using:
Histology (H&E and Masson’s trichrome staining)
Immunohistochemistry with CD34 and CD105
Digital histomorphometry the team measured epithelial thickness, collagen structure, cell/nucleus size, and microvascular density.
Key Findings
1. Thicker Gum Epithelium in Smokers
Smokers showed significantly thicker epithelial layers, with larger cells and enlarged nuclei.
This suggests that chronic exposure to tobacco chemicals triggers “adaptive” overgrowth in the tissue.
2. Reduced Collagen Density
Non-smokers had denser, healthier collagen fibers.
Smokers’ tissues showed thinning and reduced collagen organization—important because collagen provides structural support and integrity.
3. Fewer Blood Vessels, but Same Capacity for New Ones
A striking finding:
Microvascular density (MVD) was much lower in smokers
But vascular calibre and neovascular potential (CD105) were similar between groups
This means smoking reduces existing blood vessel numbers, but the tissue still retains the ability to form new vessels—an encouraging sign for healing after smoking cessation.
4. Worse Clinical Measures in Smokers
Even with similar plaque levels, smokers had:
Deeper pockets
Greater attachment loss reinforcing that smoking affects tissue health and immune response, not just plaque accumulation.
Why These Results Matter for Patients
The study paints a clear picture:
Smoking disrupts the very architecture of gum tissue—thickening the surface, weakening its collagen support, and reducing blood supply.
Yet the preserved neovascular potential offers a hopeful message:
Quitting smoking can help restore the gums’ capacity to heal.
This makes smoking cessation a critical part of periodontal treatment planning.
Conclusion
This study highlights smoking as a powerful modulator of periodontal tissue health, altering the gums at multiple biological levels. Despite these changes, the retained ability to regenerate blood vessels suggests that stopping smoking could meaningfully improve treatment outcomes.
Original Article
Title: A comparative immunohistochemical and histomorphometric analysis of human gingiva in smokers and non-smokers with periodontitis: a cross-sectional study
Journal: BMC Oral Health (2025)