Received 29.07.2025

DOI: 10.35556/idr-2025-4(113)60-69
Comparative evaluation of acid and laser etching effects on enamel structure prior to orthodontic bracket bonding
Loktionova M.V.1, ORCID: 0000-0003-3555-2035
Salman Ibrahim1, ORCID: 0000-0003-1461-8365
Dybov A.M.1, ORCID: 0000-0002-2932-168X
Kozlitina Yu.A.1, ORCID: 0000-0002-4964-7441
Hammoud M.M.1, ORCID: 0009-0004-2072-2796
Khrfan Sarah2, ORCID: 0009-0001-5048-0714
Takla Z.A.3, ORCID: 0009-0003-1611-554X
Statnik E.S.4, ORCID: 0000-0002-1105-9206
Ignatyev S.D.5, ORCID: 0000-0001-7415-5513
1 Federal State Autonomous Educational Institution of Higher Education I.M. Sechenov First Moscow State Medical University of the Ministry of Health of the Russian Federation
119048, Russia, Moscow, Trubetskaya St., 8, bld.
² North-western State Medical University named after I.I. Mechnikov
191015, Russia, Saint-Petersburg, Kirochnaya St., 41
³ Federal State Budgetary Educational Institution of Higher Education “Russian University of Medicine” of the Ministry of Health of the Russian Federation
127006, Russia, Moscow, Dolgorukovskaya St., 4
⁴ Skolkovo Institute of Science and Technology
121205, Russia, Moscow, The territory of the Skolkovo Innovation Center, Bolshoy Blvd, 30, p. 1
⁵ Federal Budgetary Establishment of Science “F.F. Erisman Federal Scientific Centerof Hygien” of the Federal Service fo Surveillance on Consumer Rights Protection and Human Well-being
141014, Russia, Moscow region, Mytishchi, Semashko, St. 2

E-mail address: salman_i@student.sechenov.ru

Summary
This study presents a comprehensive comparative analysis of human enamel surface modifications following two common pretreatment methods: conventional 37 % phosphoric acid etching and Er,Cr:YSGG laser treatment. Using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX), we examined thirty extracted premolars randomly assigned to either acid-etching or laser treatment groups. The SEM analysis revealed strikingly different surface topographies: acid etching created deep, irregular micropores and microcracks characteristic of Type I–III etching patterns, while laser treatment produced a uniform wavelike microstructure without structural damage. EDX results demonstrated significant chemical differences – the acid-etched group showed substantial calcium and phosphorus loss (Ca/P ratio dropping to 1,2–1,5) with carbon content increasing up to 40 %, indicating severe demineralization. In contrast, laser-treated specimens maintained near-physiological Ca/P ratios (~2,0) and minimal carbon incorporation (12–19 %), preserving the enamel’s chemical integrity. These findings suggest that Er,Cr:YSGG laser ablation offers a more controlled, minimally invasive surface modification technique that maintains enamel strength while creating optimal retention patterns for orthodontic bonding. The study provides compelling evidence for adopting laser technology as a superior alternative to conventional acid etching in modern orthodontic practice, particularly for patients at risk of enamel damage or demineralization

Keywords: Er,Cr:YSGG laser, phosphoric acid, enamel, SEM, EDX, etching, orthodontics, adhesion, microstructure, Ca/P.

For citation: Loktionova M.V., Salman Ibrahim, Dybov A.M., Kozlitina Yu.A., Hammoud M.M., Khrfan Sarah, Takla Z.A., Statnik E.S., Ignatyev S.D. Comparative evaluation of acid and laser etching effects on enamel structure prior to orthodontic bracket bonding. Stomatology for All / Int. Dental Review. 2025; no. 4 (113): 60–69 (in Russian). doi: 10.35556/idr-2025-4(113)60-69

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