The lingual enamel morphology and bracket shear bond strength influenced by Nd:YAG laser and aluminum oxide sandblasting preconditioning

Author(s)

Lopes, Mnica Schaffer ^[1] ; Pereira, Daisa Lima ^[2] ; Brainer de Oliveira Mota, Claudia Cristina ^[3] ; Amaral, Marcello Magri ^[4] ; Zezell, Denise Maria ^[2] ; Leonidas Gomes, Anderson Stevens ^{[5, 6]}

Affiliation

^[1] Univ Fed Pernambuco, Dept Prosthesis & Bucofacial Surg, Av Prof Moraes Rego 1235, Cidade Univ, BR-50670901 Recife, PE - Brazil

^[2] Inst Pesquisas Energet & Nucl, Ctr Lasers & Applicat, Av Prof Lineu Prestes 2242, BR-05508000 Sao Paulo, SP - Brazil

^[3] Ctr Univ Tabosa de Almeida, Sch Dent, Ave Portugal 584, BR-55016901 Caruaru, PE - Brazil

^[4] Univ Brasil, Inst Cient & Tecnol, Biomed Engn Program, Rua Carolina Fonseca 584, BR-08230030 Sao Paulo, SP - Brazil

^[5] Univ Fed Pernambuco, Grad Program Dent, Av Prof Moraes Rego 1235, Cidade Univ, BR-50670901 Recife, PE - Brazil

^[6] Univ Fed Pernambuco, Dept Phys, Av Prof Moraes Rego 1235, Cidade Univ, BR-50670901 Recife, PE - Brazil

• Document type: Journal article
• Source: CLINICAL ORAL INVESTIGATIONS; v. 25, n. 3 JUN 2020.
• Web of Science Citations: 2

Abstract

Objectives This study aimed to investigate the influence of Nd:YAG laser and aluminum oxide sandblasting on the shear bond strength (SBS) of lingual brackets and to optically analyze the behavior of the enamel morphology. Materials and methods Thirty-five bovines' incisors teeth were divided into 5 groups (n = 7), according to the surface preconditioning: G1, control group; G2, Nd:YAG laser; G3, laser + aluminum oxide sandblasting (Al2O3); G4, Al2O3; and G5, Al2O3+ laser. All groups had lingual brackets bonded and shear debonded after 72 h. SBS values were analyzed, and the enamel morphology was evaluated by optical coherence tomography (OCT) and scanning electron microscope (SEM), before and after preconditioning surface. The optical attenuation coefficient (alpha) analysis was obtained from OCT images. Data analysis used the ANOVA test, followed by post hoc Tukey, Kruskal Wallis, and post hoc Dunn tests (significance of 5%). Results The SBS values presented similarly among groups, but the value of alpha showed statistical difference (p-value = 0.0124) between G3 and G5 with the others. Optical analyses indicated a melting on the enamel that suffered laser irradiation for G2 and G5 and crystal surface disorganization for G4. Sandblasting partially removes the melting of the laser effect (G3). Conclusion The sandblasting is a dispensable step for bonding lingual brackets, and the melting of the enamel after laser irradiation does not compromise the bracket adhesive resistance. (AU)

• FAPESP's process: 05/51689-2 - Optics and Photonics Research Center at UNICAMP
• Grantee: Hugo Luis Fragnito
• Support type: Research Grants - Research, Innovation and Dissemination Centers - RIDC
• FAPESP's process: 17/50332-0 - Scientific, technological and infrastructure qualification in radiopharmaceuticals, radiation and entrepreneurship for health purposes
• Grantee: Marcelo Linardi
• Support type: Research Grants - State Research Institutes Modernization Program