Abstract
This study investigated the effect of toothbrush abrasion in all-ceramic restoration at the margin. Specimens were made of human enamel, all-ceramic (IPS Empress, IVOCLAR), and resin cement (Variolink II, VIVADENT). Sectional profile, vertical wear, and surface roughness of the luting cement were measured by a scanning laser microscope. The width of luting cement was determined to be 50, 100, 150, and 200μm. Then, the wear surface and the margin were observed on scanning electron micrographs.
Sectional profiles showed a saw-toothed line at the worn surface of luting cement. Margins of human enamel and all-ceramic were eliminated by a toothbrush, and slopes like a bevel edge were observed. There was a significant difference (t-test) between wear depth of the luting cement and the thickness of the cement line. Vertical wear of the luting cement was larger, and the cement line was thicker at the end of the toothbrush abrasion test. On the other hand, the surface roughness of luting cement was increased in all specimens.
