Although abrasives play an active role in toothpaste, they are considered an inactive ingredient because they don't reduce your risk for cavities or gum disease. However, abrasives are important ingredients because they help remove food debris and surface stains from teeth.
Ancient Egyptians and Romans used abrasives like crushed eggshells or crushed oyster shells in their toothpaste. Today's abrasives are gentler and more hygienic, like calcium carbonate, dehydrated silica gels, and hydrated aluminum oxides. These ingredients scrub and polish the surface of the teeth without damaging your tooth's enamel. Keep these abrasives in mind and ensure you aren't pressing your toothbrush too firmly against your teeth because firm brushing can damage enamel and inflame the gumline.