A mechanical device used to attach fixed or removable restorations, consisting of close-fitting male and female components. Though designs vary greatly, the female component, or matrix is typically made of metal and integrated into the abutment tooth . The male component, or patrix, is typically integrated into a pontic or removeable prosthesis.

It includes: Magnetic, Ball, Preci-vertix, ERA, Key-slide, Ceka, Swiss mar.