The following appliance is used in:
Space regaining
Maxillary arch expansion
Distalization of molar
None of the above
This is a HYRAX appliance used for maxillary arch expansion.
Several methods have been developed for RME, such as bonded Hyrax developed by McNamara and Brudon (a Hyrax with an acrylic splint bounded to the occlusal surface of posterior teeth) to minimize the vertical effects of conventional expansion appliances.