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Updated: Jan 26, 2026
06:15
Author Spotlight: Advancements and Applications in Nanoparticle Synthesis Through Laser Ablation in Liquids
Published on: June 16, 2023
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Image guided laser ablation of demineralization from root surfaces
Navitinder Dhillon1, Kenneth H Chan1, Vincent B Yang1
1University of California, San Francisco, San Francisco, CA 94143-0758.
Summary
Identifying root caries is difficult. New imaging techniques using short-wavelength infrared (SWIR) light and image-guided laser ablation offer highly selective removal of demineralized tooth tissue with minimal damage.
Area of Science:
- Dental research
- Biomedical optics
- Laser dentistry
Background:
- Demineralized root caries are challenging to detect due to factors like staining and calculus.
- Accurate identification is crucial for effective treatment and preventing further tooth decay.
Purpose of the Study:
- To develop and evaluate an image-guided laser system for selective root caries removal.
- To improve the contrast and visualization of demineralized root lesions.
Main Methods:
- Utilized short-wavelength infrared (SWIR) imaging at wavelengths beyond 1500 nm for high-contrast visualization of root caries.
- Combined a CO2 laser (9.3-μm) with a thulium-doped fiber laser (1880 nm) for selective caries ablation.
- Employed serial SWIR reflectance images for guiding the CO2 laser ablation process.
- Used cross-polarization optical coherence tomography (CP-OCT) to assess lesion depth and removed tissue volume.
Main Results:
- SWIR imaging demonstrated extremely high contrast for identifying demineralized root caries.
- The image-guided laser ablation system enabled selective removal of caries lesions.
- CP-OCT confirmed accurate assessment of lesion depth and quantified the removed sound and demineralized tissue.
Conclusions:
- Image-guided laser ablation using SWIR imaging and dual-wavelength lasers provides a highly selective method for root caries removal.
- This approach minimizes damage to surrounding healthy tooth structure.
- The technique shows promise for improved clinical management of root caries.
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