Expansion in arch has been one of the oldest means of creating space in the dental arches.
It is also one of the conservative method of gaining space.
It can also be used to correct the intermaxillary and dental arch relationships primarily in transverse direction.
It enables correction of crossbites early in treatment.
incorporate as many as teeth as possible and thus spread the load over entire alveolar length
bands can cemented simultaneously only to a few teeth
splints can adapted to all the teeth