Comparison of the Shear Bond Strengths of Ceramic Brackets Using either a Self-Etching Primer or the Conventional Method after Intracoronal Bleaching

Abstract

Objective: To evaluate the initial shear bond strengths (SBSs) of ceramic brackets using either a self-etching primer (SEP) or the conventional method (CM) after intracoronal bleaching with sodium perborate and distilled water.Methods: Eighty human incisors were divided into four groups according to bleaching and bonding procedures: Group 1, bleaching was not applied and the brackets were bonded with a self-etching primer; Group 2, bleaching was not applied and the brackets were bonded with the conventional method; Group 3, intracoronal bleaching with sodium perborate was applied for three weeks and the brackets were bonded with a self-etching primer; and Group 4, intracoronal bleaching with sodium perborate was applied for three weeks and the brackets were bonded with the conventional method. A self-etching primer (Transbond Plus) was applied as recommended by the manufacturer. After SEP application, the ceramic brackets were bonded with a light-curing adhesive (Transbond XT). For the conventional method, the teeth were etched with 37% phosphoric acid. After etching, a thin uniform coat of primer (Transbond XT Primer) was applied and the ceramic brackets were bonded with a light-curing adhesive (Transbond XT). SBSs were measured after water storage for 30 days, after 1000 cycles of thermocycling between 5°C and 55°C. Bond failure location was determined with the Adhesive Remnant Index (ARI).Results: For the SEP method, there was no significant difference between SBS values of the bleaching and non-bleaching groups. Furthermore, for the conventional method, the SBS value of the non-bleaching group was not significantly different from that of the bleaching group. SBS values of the SEP method presented significant differences from those of the conventional method (p<0.001). SBS values of SEP application decreased with and without bleaching. The ARI scores did not show any significant difference among the groups (p=0.174). Conclusion:Intracoronal bleaching with sodium perborate and distilled water did not affect the SBS values of ceramic brackets.

Evaluation of Adhesive Remnant Index after metal brackets removal using AutoCAD software

“…Nekoliko faktora utiču na jačinu veze između zuba i bravica: vrsta adhezivnih sistema koji se koriste za lepljenje bravica, vrsta kiseline i dužina perioda kondicioniranja gleđi tokom pripreme zuba, veličina i vrsta bravica, dizajn baze bravice i prisustvo pljuvačke, odnosno mogućnost obezbeđivanja suvog radnog polja tokom sprovođenja postupka postavke fiksnog ortodontskog aparata. Navedeni faktori, zajedno sa vrstom i načinom primene instrumenata za uklanjanje bravica, utiču na način prekida veze između zuba i bravica, a samim tim i na količinu preostalog adheziva na zubima i na bravicama [3][4][5][6].…”

“…Several factors may influence enamel-bracket shear bond strength: the type of adhesive systems used for bonding brackets, the type and duration of enamel etching, the size and type of brackets, the design of bracket base and oral environmental factors. These factors and the type of debonding procedure affect the type of bond failure between teeth and brackets as well as the amount of remaining adhesive on both [3][4][5][6].…”