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Effects of laser and fluoride on the prevention of enamel demineralization: an in-vitro study

Nastaran Chokhachi Zadeh Moghadam, Bahman Seraj, Nasim Chiniforush, Sara Ghadimi




Introduction: Investigations have demonstrated that fluoride is an essential element in preventive dentistry. However, there are still controversies about the preventive effects of various kinds of laser. The aim of this study was to examine the effect of diode laser irradiation (810 nm) with or without fluoride therapy in the prevention of deciduous enamel demineralization.
Methods: Sixty deciduous molar crowns were randomly assigned to 6 groups: C: received no treatment; F: fluoride varnish application; 2L: 2 times diode laser irradiation; 4L: 4 times diode laser irradiation; F2L: 2 times laser irradiation over fluoride varnish; F4L: 4 times laser irradiation over fluoride varnish. Teeth in all groups were subjected to a pH-cycling process to produce artificial caries-like lesions.
Results: The analysis of variance (ANOVA) of microhardness values indicated a significant great effect for laser, fluoride, and the interaction of laser- fluoride on reducing the final microhardness value (P < 0.001). However, the 2L group was an exception. Despite the 4L group, it did not show a significant prevention of enamel microhardness loss (P = 0.125). These 2 groups exhibited different effects in the absence of fluoride (P2L-4L = 0.05) while in the presence of the fluoride varnish, no statistically significant difference was observed between them (PF2L-F4L = 0.257). Moreover, no statistically significant difference was observed between the laser-fluoride combination group and the fluoride group (PF2L-F = 0.133, PF4L-F = 0.926).
Conclusion: Our results suggest that fluoride varnish, diode laser, and their combination decrease the loss of the enamel microhardness value and potentially prevent deciduous enamel demineralization. However, the combination of laser and fluoride was not more effective than fluoride.


Diode laser; Fluoride; Primary tooth; Demineralization


Petersen PE. The World Oral Health Report 2003: continuous improvement of oral health in the 21st century- -the approach of the WHO Global Oral Health Programme. Community Dent Oral Epidemiol. 2003;31 Suppl 1:3-23.

Hugo FN, Vale GC, Ccahuana-Vasquez RA, Cypriano S, de Sousa Mda L. Polarization of dental caries among individuals aged 15 to 18 years. J Appl Oral Sci. 2007;15(4):253-258.

Hardwick K, Barmes D, Writer S, Richardson LM. International collaborative research on fluoride. J Dent Res. 2000;79(4):893-904. doi:10.1177/00220345000790040301

Marinelli CB, Donly KJ, Wefel JS, Jakobsen JR, Denehy GE. An in vitro comparison of three fluoride regimens on enamel remineralization. Caries Res. 1997;31(6):418-422. doi:10.1159/000262432

Maguire A. ADA clinical recommendations on topical fluoride for caries prevention. Evid Based Dent. 2014;15(2):38-39. doi:10.1038/sj.ebd.6401019

Pandit S, Kim JE, Jung KH, Chang KW, Jeon JG. Effect of sodium fluoride on the virulence factors and composition of Streptococcus mutans biofilms. Arch Oral Biol. 2011;56(7):643-649. doi:10.1016/j.archoralbio.2010.12.012

Professionally applied topical fluoride: evidence-based clinical recommendations. J Am Dent Assoc. 2006;137(8):1151-1159.

Carey CM. Focus on fluorides: update on the use of fluoride for the prevention of dental caries. J Evid Based Dent Pract. 2014;14 Suppl:95-102. doi:10.1016/j.jebdp.2014.02.004

Featherstone JD. Delivery challenges for fluoride, chlorhexidine and xylitol. BMC Oral Health. 2006;6 Suppl 1:S8. doi:10.1186/1472-6831-6-s1-s8

Esteves-Oliveira M, Zezell DM, Meister J, et al. CO2 Laser (10.6 microm) parameters for caries prevention in dental enamel. Caries Res. 2009;43(4):261-268. doi:10.1159/000217858

Ana PA, Bachmann L, Zezell DM. Lasers effects on enamel for caries prevention. Laser Phys. 2006;16(5):865-875. doi:10.1134/s1054660x06050197

Korytnicki D, Mayer MP, Daronch M, Singer Jda M, Grande RH. Effects of Nd:YAG laser on enamel microhardness and dental plaque composition: an in situ study. Photomed Laser Surg. 2006;24(1):59-63. doi:10.1089/pho.2006.24.59

Can AM, Darling CL, Ho C, Fried D. Non-destructive assessment of inhibition of demineralization in dental enamel irradiated by a lambda=9.3-microm CO2 laser at ablative irradiation intensities with PS-OCT. Lasers Surg Med. 2008;40(5):342-349. doi:10.1002/lsm.20633

Zancope BR, Rodrigues LP, Parisotto TM, Steiner- Oliveira C, Rodrigues LK, Nobre-dos-Santos M. CO2 laser irradiation enhances CaF2 formation and inhibits lesion progression on demineralized dental enamel-in vitro study. Lasers Med Sci. 2016;31(3):539-547. doi:10.1007/s10103- 016-1900-4

Vitale MC, Zaffe D, Botticell AR, Caprioglio C. Diode laser irradiation and fluoride uptake in human teeth. Eur Arch Paediatr Dent. 2011;12(2):90-92.

Gonzalez-Rodriguez A, de Dios Lopez-Gonzalez J, del Castillo Jde D, Villalba-Moreno J. Comparison of effects of diode laser and CO2 laser on human teeth and their usefulness in topical fluoridation. Lasers Med Sci. 2011;26(3):317-324. doi:10.1007/s10103-010-0784-y

Santaella MR, Braun A, Matson E, Frentzen M. Effect of diode laser and fluoride varnish on initial surface demineralization of primary dentition enamel: an in vitro study. Int J Paediatr Dent. 2004;14(3):199-203. doi:10.1111/ j.1365-263X.2004.00550.x

Klim JD, Fox DB, Coluzzi DJ, Neckel CP, Swick MD. The diode laser in dentistry. Rev Wavelengths. 2000;8:13-6.

da Silva Barbosa P, da Ana PA, Poiate IA, Zezell DM, de Sant’ Anna GR. Dental enamel irradiated with a low-intensity infrared laser and photoabsorbing cream: a study of microhardness, surface, and pulp temperature. Photomed Laser Surg. 2013;31(9):439-446. doi:10.1089/ pho.2013.3485

de Sant’Anna GR, dos Santos EA, Soares LE, et al. Dental enamel irradiated with infrared diode laser and photo-absorbing cream: part 2--EDX study. Photomed Laser Surg. 2009;27(5):771-782. doi:10.1089/pho.2008.2401

De Menezes Oliveira MA, Torres CP, Gomes-Silva JM, et al. Microstructure and mineral composition of dental enamel of permanent and deciduous teeth. Microsc Res Tech. 2010;73(5):572-577. doi:10.1002/jemt.20796

Dean JA. McDonald and Avery’s Dentistry for the Child and Adolescent. 10th ed. Elsevier, Health Sciences Division; 2016.

Wang LJ, Tang R, Bonstein T, Bush P, Nancollas GH. Enamel demineralization in primary and permanent teeth. J Dent Res. 2006;85(4):359-363. doi:10.1177/154405910608500415

Azevedo DT, Faraoni-Romano JJ, Derceli Jdos R, Palma- Dibb RG. Effect of Nd:YAG laser combined with fluoride on the prevention of primary tooth enamel demineralization. Braz Dent J. 2012;23(2):104-109.

Liu JF, Liu Y, Stephen HC. Optimal Er:YAG laser energy for preventing enamel demineralization. J Dent. 2006;34(1):62- 66. doi:10.1016/j.jdent.2005.03.005

Hsu CY, Jordan TH, Dederich DN, Wefel JS. Laser-matrix-fluoride effects on enamel demineralization. J Dent Res. 2001;80(9):1797-1801. doi:10.1177/002203450108000905 01

Correa-Afonso AM, Bachmann L, de Almeida CG, Dibb RG, Borsatto MC. Loss of structural water and carbonate of Nd:YAG laser-irradiated human enamel. Lasers Med Sci. 2015;30(4):1183-1187. doi:10.1007/s10103-014-1532-5

Correa-Afonso AM, Bachmann L, Almeida CG, Corona SA, Borsatto MC. FTIR and SEM analysis of CO2 laser irradiated human enamel. Arch Oral Biol. 2012;57(9):1153- 1158. doi:10.1016/j.archoralbio.2012.02.004

Ying D, Chuah GK, Hsu CY. Effect of Er:YAG laser and organic matrix on porosity changes in human enamel. J Dent. 2004;32(1):41-46.

Zancope BR, Cesar MM, Rodrigues LK, Nobre-Dos- Santos M. Evaluation of the effect of a CO2 laser and fluoride on the reduction of carious lesions progression in primary teeth: an in vitro study. Proc SPIE Int Soc Opt Eng. 2014;8929:89290K. doi:10.1117/12.2037284

Hsu CY, Jordan TH, Dederich DN, Wefel JS. Effects of low-energy CO2 laser irradiation and the organic matrix on inhibition of enamel demineralization. J Dent Res. 2000;79(9):1725-1730. doi:10.1177/002203450007900914 01

Souza MR, Watanabe IS, Azevedo LH, Tanji EY. Morphological alterations of the surfaces of enamel and dentin of deciduous teeth irradiated with Nd:YAG, CO2 and diode lasers. Int J Morphol. 2009;27(2):441-446. doi:10.4067/S0717-95022009000200021

DOI: https://doi.org/10.22037/jlms.v9i3.17176