Abstract: An anticalculus oral composition, which is preferably a toothpaste or a mouthrinse, includes an effective anticalculus azacycloalkane-2,2-diphosphonic acid or a salt thereof, preferably azacycloheptane-2,2-diphosphonic acid, and a water-soluble or water swellable polymer having a molecular weight of about 1,000-2,000,000, such as a linear copolymer of maleic anhydride and vinyl methyl ether or a polyvinyl phosphonate. The polymer surprisingly increases the anticalculus effectiveness of the azacycloalkane-2,2-diphosphonic acid or salt thereof in such compositions, even at comparatively low concentrations of both such materials. Also within the invention is a process for applying such compositions to the teeth, and it has been shown by both in vitro and in vivo testing that significant repeatable improvements in anticalculus effects are obtained by such processes, compared to control processes in which either of the active components mentioned is employed alone in the described oral compositions.