Hi, whatever we eat forms a layer on teeth known as plaque & calculus on enamel. As we do scaling, some flecks of plaque and calculus remains which makes tooth surface rough and susceptible for more plaque deposition. Polishing of teeth with some abrasives same as in toothpaste helps in removing those small particles and flecks of calculus making tooth surface gain it's lustre back. It restores teeth enamel to its natural smoothness.

Teeth polishing is a process generally performed after scaling (oral prophylaxis or teeth cleaning). This process makes the surface smoother than before so that there are lesser chances of plaque accumulation.