Abstract

RAMIREZ SANCHEZ, Hermes Ulises; RUBIO CASTILLON, Dora María; VALENCIA TORO, Fredy Alejandro  and  GARCIA LOPEZ, Eliezer. Comparación del esfuerzo a la tracción de brackets arenados mediante óxido de aluminio nuevo y reciclado con y sin ultrasonido (estudio in vitro).. Acta odontol. venez [online]. 2008, vol.46, n.1, pp.15-19. ISSN 0001-6365.

Faults in the adhesion of brackets occur frequently and generally the use of a new bracket is required. With the introduction of the sanded technique it has been demonstrated that the brackets can be reused by subjecting them to a cleaning process, thereby improving adhesion. The objective of the study is comparer the tensile strength to the brackets sanded by means of new and recycled aluminum oxide, both with and without ultrasound. The assessment of tensile strength of the new and recycled base of brackets subjected to a sanding process of with new and recycled aluminum oxide in Instrom universal test machine of 80 first and second human premolars, divided in 5 groups of 16-piece: (C) used new brackets,  (AN) used new aluminum oxide  sanded brackets,  (AN+U) new aluminum oxide sanded plus ultrasound, (AR) recycled sanded, and (AR+U) recycled sanded plus ultrasound. The same type of brackets and adhesion system were used in all groups. It was demonstrated that the brackets AN increased the tensile strength and it increases even more when putting the attachments to an ultrasonic bath.  In the case of AR, their tensile strength diminished considerably, but when put under the ultrasonic bath, values were very close to those of the control group.  The t-student test, it was found that groups C vs. AN, AN vs. AN+U, and C vs. AR+U did not have significant statistical differences.  However, in groups C vs. AN+U, C vs. AR, AN vs. AR, AN vs. AR+U, AN+U vs. AR+U statistically significant differences were found. The tensile strength analysis allow concluding that the best preparation of the base technique is to use a bath in an ultrasound device with 100% ethylic alcohol for 5 minutes after being sanded with new aluminum oxide.

Keywords : Brackets; sanded; tensile strength; new and recycled aluminum oxide; ultrasound.