Influence of the mechanical factor in the formation of non-carious cervical lesions

Abstract

Background: non-carious cervical lesions are multifactorial, the action of acids, abrasives and mechanical loads at a distance from the lesion site. It is necessary to explain the mechanism of action of distant loads. This study proposed to evaluate the penetration of silver nitrate 10%, to the enamel of specimens subjected or not to cyclic loading. Method: 60 bovine incisors were cut into 3x3x8.2 mm parallelepipeds with 2x2 mm dentin notching, protected from nitrate with varnish, except for a 1.5x5 mm enamel strip, 1200 mechanical cycles of tension or compression were applied, With 5 s of 40 N load and 25 s without load, a control group received neither load nor exposure to the tracer, another control group received exposure to the tracer without load, to locate the tracer they were radiographed, tomographed and observed under magnifying glass with reflected and transmitted light. Results: the radiographs only showed the highest concentration of the tracer, the microtomography was ineffective due to the artifacts formed, the observation under magnification indicated variations in the natural coloration of the enamel, the specimens exposed to the tracer showed a thin layer of infiltration and variations in the penetration pattern. This inconvenience to identify if there was pumping or not, could be explained by differences in the speed and depth of the enamel of the different molecules such as acids. Conclusions: the tracer penetrated the enamel without differences in the penetration pattern.