Influence of mechanicalload cycling on the cervical microleakage of composite resin restorations associated to self-etching adhesive system

Abstract

The objective of this in vitro study was to evaluate the influen- ce of mechanical load cycling on the cervical microleakage ofa self- etching adhesive system (Prornpt- L-Pop / 3MESPE) in 160 Class II molar restorations, using a con- densable composite (Filtek P60 / 3M ESPE). All specimens were divided into four groups (1, 2, 3, 4), accordingto the number ofmecha- nical cyclesused (O, 10,50 and 100 cycles, respectively). Each group was divided into two subgroups (A and B), according to the use or not of etching (37% phosphoric acid) previously to the application of the adhesive system. During the mechanicalload cycling, all speci- mens were immersed in a dye agent (0,5%blue methilene). AlI specimens were sectioned for the evaluation of leakage levels. The results showed that 50 cyclesis the proper number for microleakage tests which use mechanical load cycling, besides, the previous etching is recommended when using self-etching adhesives systems.