Comparative study of dental enamel loss after debonding braces by analytical scanning electron microscopy (SEM).
Clinical procedures when shear forces are applied to brackets suggest adhesion forces between 2.8 and 10.0 MPa as appropriate. In this study dental enamel was evaluated by scanning electron microscopy (SEM) before and after removing the brackets. Thirty bicuspids (previous prophylaxis) with metallic brackets (Roth Inovation 0.022 GAC), Transbond Plus SEP 3M Unitek adhesive and Transbond XT 3M resin were used. The samples were preserved to 37°C during 24 hr and submited to tangential forces with the Instron Universal machine 1.0 mm/min speed load strength resistance debonding. Also the Adhesive Remanent Index (ARI) test was made, evaluating the bracket base and the bicuspid surface. All the bracket SEM images were processed with AutoCAD to determine the enamel detached area. The average value was 6.86 MPa (SD ± 3.2 MPa). ARI value 1= 63.3%, value 2= 20%, value 3= 13.3% and 33% presented value 0. All those samples with dental enamel loss, presented different situations as fractures, ledges, horizontal, and vertical loss in some cases, and some scratch lines. There is no association between the debonding resistance and enamel presence. Less than half of the remanent adhesive on the dental enamel was present in most of the samples when the ARI test was applied. When the resin area increases, the debonding resistance also increases, and when the enamel loss increases, the resin free metallic area of the bracket base decreases in the debonding.
División de Estudios de Posgrado e Investigación. Facultad de Odontología, Universidad Nacional Autónoma de México, D.F. México.
Jacqueline Adelina
http://orcid.org/0000-0003-1010-5044
JA
Rodríguez-Chávez
Departamento de Materia Condensada, Instituto de Física. Universidad Nacional Autónoma de México, D.F. México.
Jesús
J
Arenas-Alatorre
Facultad de Odontología, Universidad Autónoma de Sinaloa, Culiacán, México.
Irma Araceli
IA
Belio-Reyes
D000268:Adhesiveness; D017438:Bisphenol A-Glycidyl Methacrylate; D001915:Braces; D001840:Dental Bonding; D017005:Dental Debonding; D003743:Dental Enamel / Q000648:ultrastructure*; D003799:Dental Stress Analysis; D006801:Humans; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D016910:Orthodontic Brackets; D019279:Resin Cements; D033081:Shear Strength; D013499:Surface Properties
D019279:Resin Cements; C477790:Transbond XT; C065742:Transbond; D017438:Bisphenol A-Glycidyl Methacrylate
SEM; debonding forces; enamel; enamel loss; self-etch adhesive; shear bond strength