Damien Storey - Materials

Components Of Removable Applaince
1.  Active Components (Anchorage)
Screws
– Uni-dimensional screws
– Bi-dimensional screws

Wire springs
– Finger spring
– Z-spring
– Canine retractor
– Short labial arch.
Screws
– Expansion is 1 mm. per one full turn i.e. 0.25 mm. per quarter turn
– May be used for moving one tooth or group of teeth (usually more
than one tooth to be moved with a screw)
– Have different sizes and range of activation
– Useful only when a few millimeters of space is needed
– Usually jackscrews been used as active component
– Clasps for retention
Expansion screws
– For anterior Expn. of Max. incisors
– For simultaneous Expn. of maxillary
incisors anteriorly and posteriors laterally
(Y-plate).
– Y-plate can be modified for Tx. Of
unilateral x-bite
– Maxillary split plate (By post. teeth tipping
not by opening mid-palatal suture).
Active plate
• The simplest uses of an active plate is to correct a maxillary anterior crossbite.
• Posterior biteplane is necessary in adult to allow clearance for the upper incisor to move out of crossbite (½ crown or more is covered).
Active plate split in midline will expand constricted maxillary arch almost totally by tipping the posterior teeth buccally Not by opening mid-palatal suture. Therefore this appliance is not indicated for skeletal crossbites or dental expansion for more than 2 mm per side.

1. Springs
– Provide extra length of wire to increase range of action and resiliency
– Extra length can be provided in the form of coil (s), loop (s) or change configuration to provide extra length
of the wire
2.   Retentive Components
– Adam’s clasp
– C-clasp (Circumferential clasp)
– Lingual extension clasp
– Ball clasp

3.  Acrylic Base Plate
It is used as a vehicle to carry all
Removable Appliance components together.
• It is the Anchor tool for tooth movement.
• Use self-curing acrylic resin.