Detection of carious lesion by laser speckle analysis using the first order moment




Laser speckle imaging; Diagnostic; Computer vision; Dental Caries.


Carious lesion is one of the most prevalent diseases in humankind, affecting nearly all human beings at least once in a lifetime. Early carious lesion (ECL, also known as white spot lesion) is part of the caries process in which the enamel surface loses mineral but the subsurface layer overlying the mineral-poor region remains intact. In its early stages, the detection of the carious lesion is currently still a major challenge because it is based on visual inspection, thus with an inherent subjectivity. In this work, we present a method to detect and assess the severity of ECLs using a computer-assisted laser speckle imaging technique. Forty-five polished and cut bovine incisors samples allow a paired t-test by exposing half of the surface while protecting the other half. The samples, included in a PVC tube, were immersed in 50ml of a solution (pH 5.0) containing 0.05M acetate buffer solution and 50% saturated hydroxyapatite enamel powder at 37°C. The etching time is 24h; 48h and 72h; each group contain 15 samples. We illuminate each sample with a laser and analyse the first momentum of the laser speckle images with a computer. Our results shows that the first momentum of the LSI of the sound region statistically differs from the decay region of the samples for all groups (p<0.0001). We also found a strong correlation between the acid etch duration (severity of the decay) and the shift in LSI contrast (Pearson’s correlation coefficient ρ=0.9989, R²=0.9978). Detecting decay in its early stages is still a challenge in the clinical practice, however this work demonstrates that the analysis of the statistical features of the laser speckle image in the spatial domain allows for the detection of microstructural changes in the enamel associated with the presence of the lesion even before any intervention is required.


Araujo, A. A., Braca, L. S., Dietrich, L., Caixeta, D. A. F., Santos-Filho, P. C. F., & Martins, V. M. (2020) Caries detection and diagnosis methods: a narrative review. Research, Society and Development 9 (11)

Araujo, G. S. A., & Sfalcin, R. A. (2013). Evaluation of polymerization characteristics and penetration into enamel caries lesions of experimental infiltrants. Journal of Dentistry 41 1014 – 1019

Arends, J., & Christoffersen, J. (1986). The Nature of Early Caries Lesions in Enamel. First Published January 1.

Bakhmutov, D., Gonchukov, S., Kharchenko, O., Nikiforova, O., & Yu, V. (2004). Early dental caries detection by fluorescence spectroscopy. Laser Physics Letters, 1, , Published 23 August

Briers, J. D. (2001). Laser Doppler, speckle and related techniques for blood perfusion mapping and imaging. Physiological Measurement, Bristol, 22(4), 35-66.

Cruz, I. C., Neto, M. M. G., Lima, W. T. S., Silva, W. A., & Hora, S. L. (2020). New diagnostic methods for detecting dental caries - Integrative review. Research, Society and Development 9 (10)

Deana, A. M., Jesus, S. H. C., Koshoji, N. H., Busadori, S. K., & Oliveira, M. T. (2013) Detection of early carious lesions using contrast enhancement with coherent light scattering (speckle imaging). Laser Physics, 23, 075607

Estellano, G. P., Bussadori, S. K., Guedes, C. C., Fernandes, K. P. S., Martins, M. D., & Haro, G. H. (2007) . Identificación clínica de las zonas de la dentina cariada. In: Gilberto Henostroza Haro et al.. (Org.). Caries Dental - principios y procedimientos para el diagnóstico. (2a ed.) Madri: Ripano Editorial Médica, 1, 53-68.

Featherstone, J. D. B. (2009); Remineralization, the Natural Caries Repair Process—The Need for New Approaches. 21(1), 4-7

Ismail, A. I., Sohn, W., Tellez, M., Amaya, A., Sen, A., Hasson, H., & Pitts, N. B. (2007). The International Caries Detection and Assessment System (ICDAS): an integrated system for measuring dental caries. Community Dent Oral Epidemiol 35(3), 170–178

Karlsson, L. (2010). Caries detection methods based on changes in optical properties between healthy and carious tissue. Int J Dent. 2010:270729. E pub. Mar 28

Kishen, A., Shi, Z., Shrestha, A., & Neoh, K. G. (2008). An investigation on the antibacterial and antibiofilm efficacy of cationic nanoparticulates for root canal disinfection. J Endod. Dec;34(12), 1515-20.

Koshoji, N. H., Bussadori, S. K., Bortoletto, C. C., Oliveira, M. T., Prates, R. A., & Deana, A. M. ( 2015A). Analysis of eroded bovine teeth through laser speckle imaging. In Lasers in dentistry XXI 2015 Feb 24 (Vol. 9306, p. 93060D). International Society for Optics and Photonics

Koshoji, N. H., Bussadori, S. K., Bortoletto, C. C., Prates, R. A., Oliveira, M. T., & Deana, A. M. (2015B) Laser speckle imaging: a novel method for detecting dental erosion. PLoS One 10(2), e 0118429.

Koshoji, N. H., Prates, R. A., Bussadori, S. K., Bortoletto, C. C., De Miranda, W. G., Librantz, A. F. H., Lima, L. C.R, Oliveira, M. T., & Deana, A. M. Relationship between analysis of laser speckle image and Knoop hardness on softening enamel. Photodiagnosis and Photodynamic Therapy (Print), 15.

Langhorst, S. E., O'Donnell, J. N., & Skrtic, D. (2009). In vitro remineralization of enamel by polymeric amorphous calcium phosphate composite: quantitative microradiographic study. Dent Mater 25:884–891

Mosby, A. N. (2003). Ten Cate's Oral Histology: Development, Structure, and Function. Volume 1

Nyvad, B., Machiulskiene, V., & Baelum, V. (1999). Reliability of a new caries diagnostic system differentiating between active and inactive caries lesions.. Caries Res. 33(4), 252-60

Rocha, G. T. C., Borges, A. B., Torres, L. M., Gomes, I. S., & de Oliveira, R. S. (2011). Effect of caries infiltration technique and fluoride therapy on the colour masking of white spot lesions. J Dent. Mar; 39(3), 202-7.

Silverstone, L. M. (1977). Remineralization phenomena. Caries Res 11(Suppl 1):59–84

White, S. C., & Pharoah, M. J. (2009). Oral Radiology - E-Book: Principles and Interpretation. Elsevier, New York, NY, USA.

World Health Organization; The World health report : 2003 : shaping the future




How to Cite

SILVA, J. V. P. da; SFALCIN, R. A.; ANDRIANARIJAONA, V. M. .; GAVINHO, L. G. .; SALVIATTO, L. T. C. .; BUSSADORI, S. K. .; DEANA, A. M. . Detection of carious lesion by laser speckle analysis using the first order moment. Research, Society and Development, [S. l.], v. 9, n. 12, p. e22491211039, 2020. DOI: 10.33448/rsd-v9i12.11039. Disponível em: Acesso em: 24 jun. 2024.



Health Sciences