Intradental Attachments
Intradental Attachments are housed within the crown or root structure of the natural tooth, and we can classify them into two further groups, depending on the type of retentive mechanism used: magnetic and frictional (with a tapered design, parallel-walled boxes and tubes, adjustable metal plates, springs, studs or locks).
Extradental Attachments
Extradental Attachments can also be divided into two further groups: bar attachment and cantilever, which can be rigid or mobile. For example, CEKA and VKS (Bredent).