UCSF

Objective

The purpose of this study was to determine the feasibility of image-guided laser ablation of demineralization from tooth occlusal surfaces using coaxial near-infrared (NIR) and CO₂ lasers.

Materials and methods

A CO₂ laser operating at a wavelength of 9.3-μm was combined with a thulium-doped fiber laser operating at 1880-nm for the selective removal of simulated occlusal caries lesions from 10 tooth samples. Serial NIR reflectance images at 1880-nm were used to guide the CO₂ laser for image-guided laser ablation. Polarization-sensitive optical coherence tomography (PS-OCT) was used to assess the initial depth of the lesions before removal and assess the volume of sound and demineralized tissue removed by the CO₂ laser.

Results

PS-OCT scans indicated that roughly ∼99% of the lesion was removed by image-guided laser ablation. A mean volume of 0.191-mm³ or 11.9-μm/voxel of excess enamel was removed during lesion removal.

Conclusion

A co-aligned NIR/CO₂ laser scanning system has great potential for the highly selective removal of dental decay (demineralization). Lasers Surg. Med. 51:176-184, 2019. © 2018 Wiley Periodicals, Inc.