CC BY 4.0 · Eur J Dent 2022; 16(01): 64-79
DOI: 10.1055/s-0041-1731628
Original Article

Beam Profiling of Dental Light Curing Units Using Different Camera-Based Systems

Mateus Garcia Rocha
1   Operative Dentistry Division, Department of Restorative Dental Sciences, College of Dentistry, University of Florida, Florida, United States
Dayane Oliveira
1   Operative Dentistry Division, Department of Restorative Dental Sciences, College of Dentistry, University of Florida, Florida, United States
Christopher Felix
2   Bluelight Analytics Inc., Nova Scotia, Canada
Jean-François Roulet
1   Operative Dentistry Division, Department of Restorative Dental Sciences, College of Dentistry, University of Florida, Florida, United States
Mário Alexandre Coelho Sinhoreti
3   Dental Biomaterials Division, Department of Restorative Dentistry, Piracicaba Dental School, State University of Campinas, Sao Paulo, Brazil
Américo Bortolazzo Correr
3   Dental Biomaterials Division, Department of Restorative Dentistry, Piracicaba Dental School, State University of Campinas, Sao Paulo, Brazil
› Author Affiliations
Funding This study was partially supported by Fundação de Ampáro a Pesquisa do Estado de São Paulo (grant 2016/06019–3, 2017/22195–9, 2016/05823–3, and 2017/22161–7).


Objective This study aimed to perform the beam profile of dental light-curing units (LCUs) using mirrorless and smartphone cameras and correlate it to a camera-based laser beam profiling system.

Materials and Methods Three LCUs were evaluated (Radii Plus; Bluephase G2; and VALO Cordless). The spectral power of the LCUs was measured by using a spectrophotometer. The light emitted from the LCUs was projected onto a glass diffuser, and the images were recorded by using a mirrorless camera (NEX-F3), a smartphone (iPhone) and a camera-based beam profiler. Bandpass optical-filters were used, and for each LCU, the total spectral power output was integrated to calibrate the images. Statistical analysis was performed by digital image correlation (pixel by pixel) using Pearson’s correlation (α = 0.05; β = 0.2).

Results The beam profile images showed nonuniform radiant emittance and spectral emission distributions across all the LCUs light tip. A strong correlation was found among cameras (Pearson’s r = 0.91 ± 0.03 with 95% confidence interval [CI]: 0.88–0.94 for the NEX-F3 and Pearson’s r = 0.88 ± 0.04 with 95% CI: 0.84–0.92 for the iPhone).

Conclusion The standard Ophir beam profile system presented the most accurate distribution, but the mirrorless and smartphone cameras presented a strong correlation in the irradiance distribution of the beam profile images. Alternative cameras can be used to perform light beam profile of dental LCUs, but caution is needed as the type of sensor, image bit depth, and image processing are important to obtain accurate results.

Publication History

Article published online:
27 August 2021

© 2021. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (

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