Light Curing Makes SDF Stronger: A Faster Way to Halt Tooth Decay
Understanding the Challenge
Tooth decay remains one of the most common oral health problems worldwide. Among various treatment options, silver diamine fluoride (SDF) stands out for being simple, painless, and cost-effective. Dentists often use it for young children or patients who struggle to sit still during longer procedures.
However, the recommended 60-second SDF application time can still feel long—especially for uncooperative or anxious patients. This raised a key question for researchers:
Can SDF work effectively in a shorter time—and can light curing help enhance its effect?
What the Researchers Wanted to Find Out
Researchers from Chulalongkorn University conducted an in-vitro study to test how SDF performs when applied for:
10 seconds vs. 60 seconds
With or without 20 seconds of light curing
They evaluated three important indicators of how well SDF stops tooth decay:
Reduction in lesion depth (how much the decay stops progressing)
Increase in mineral density (how much stronger the tooth becomes)
Penetration depth of SDF (how deeply SDF enters the dentin)
How the Study Was Conducted
Researchers created standardized artificial dentin caries on extracted molars, then divided them into four groups:
SDF60 — 60 seconds, no light curing
SDF10 — 10 seconds, no light curing
SDF60LC — 60 seconds + light curing
SDF10LC — 10 seconds + light curing
They used micro-CT imaging, microscopic analysis, and elemental profiling to observe how SDF behaved under each condition.
Key Findings
1. Light curing significantly boosts SDF performance
Samples that underwent light curing showed:
deeper SDF penetration
greater reduction in lesion depth
higher mineral density
compared with samples that received SDF alone.
2. The best results came from 60 seconds of SDF + light curing
The SDF60LC group produced the strongest overall outcomes, showing:
the deepest silver penetration,
the most mineral gain, and
the greatest arrest of lesion progression.
3. Shorter application becomes more effective when paired with light curing
The 10-second application alone (SDF10) was the least effective.
But adding light curing (SDF10LC) dramatically improved the results:
Penetration depth increased significantly
Some parameters reached levels similar to the 60-second SDF application
This suggests a viable, shorter protocol for cases where patient cooperation is limited.
What This Means for Dental Care
While the standard 60-second SDF application remains the most effective, this study shows that:
Light curing enhances SDF, making it more protective
A 10-second SDF application + 20-second light curing may serve as a practical alternative for young children, special-needs patients, or situations requiring reduced chair time
However, real-world effectiveness still needs to be confirmed through clinical trials.
Conclusion
This study highlights how light curing can strengthen and accelerate the action of SDF, potentially transforming how dentists manage caries in challenging patient populations. A faster, light-assisted approach may make SDF even more accessible, efficient, and patient-friendly—especially where treatment time is critical.
Original Article
Phuensuriya J., Thanyasrisung P., Trairatvorakul C., Punyanirun K., & Techatharatip O. (2025). The impact of light curing on the efficacy of silver diamine fluoride in arresting dentinal caries: an in vitro study. BMC Oral Health, 25:1792.
DOI: https://doi.org/10.1186/s12903-025-07177-7