Adaptation of resin restorative materials to etched enamel and the interfacial work of fracture

Scanning electron microscope appearance of the enamel/composite/bracket areas using different methods of surface enamel treatment, composite mix and bracket loading

Minimal plaque retention on and around orthodontic brackets is of paramount importance if iatrogenic tooth damage is to be avoided. This study made use of the scanning electron microscope to examine how variations in composite mix and finishing affected the smoothness and adaptation at the bracket, composite, and enamel interfaces. The study indicated that the optimum choice for good composite/enamel adaptation with a smooth composite surface and good composite/bracket adaptation involves the use of an intermediate unfilled resin layer, a paste/liquid mix of composite placed on a bracket which is optimally loaded, and no excess composite removed with an instrument.