The aesthetic success and longevity of composite restorations depend on their ability to reflect light like natural tooth enamel and to be smooth enough to prevent the accumulation of bacterial plaque. After the restoration is complete, aluminum oxide-coated finishing and polishing discs should be applied in a strict sequence from coarse to fine (typically from coarse to super-fine, e.g., from 40 microns to 1-5 microns). Each disc progresses by removing the micro-scratches left on the surface by the previous, thicker disc; if this sequence is skipped, or if excessive pressure is applied to the discs at very high speeds, creating localized heating (thermal damage) in the composite matrix, macro-cracks will remain on the filling surface. This will allow agents such as tea and coffee to quickly penetrate the filling, causing the aesthetic appearance to be completely lost within a few months.
