Excellent removable appliances for patients requiring anterior improvement. These appliances provide the desirable features of esthetics and simplicity of adjustment. The patient will become accustomed to the appliance if it is placed without pressure for the first week. Springs are usually adjusted monthly with a variance of one and one-half millimeters between the active and passive positions. The time required for movement as a result of appliance pressure varies between patients. Lack of movement would usually indicate the need for a more extended period of pressure rather than greater pressure. Minimal spring adjustments avoid appliance displacement.
Labial movement
and/or rotation of the anteriors can be effected by the lingual finger spring; double helical type springs provide greater adjustment range, flexibility, and control. A small #139 Birdbeak plier is usually effective for many of these adjustments. For rotational movements, the round portion of the plier is inserted into the coil, and the spring rotated. By adjusting the second coil in a similar fashion, the spring is positioned for straight-line labial movement of the anterior. The labial arch wire enhances proper arch form.
Mesial and/or distal movement
of the centrals, laterals or cuspids can be effected by the looped finger springs. One side of the loop is free-sliding. Opening the loop will advance the spring extension against the tooth and provide a constant, gentle pressure to move the anterior in the desired direction. Spring extensions placed near the gingival can minimize tipping. If tight contact points prevent spring extension placement, separators can be inserted one week prior to appliance placement.
Lingual movement
of the anteriors can be effected by the finger springs on the labial wire. With the #139 plier supporting the solder joint finger pressure can be used to skew the spring in the direction of movement. The loops in the cuspid areas can be crimped occasionally to keep pace with and retain improvement. Typically, the labial wire will not be adjusted to exert pressure against the anteriors, as this will result in a loss of retention and appliance displacement.
Modified Hawley removable
appliance is frequently the appliance of choice on adult cases with flared maxillary incisors. Elastic hooks are soldered to the labial bow at the omega loops. With two ounce elastic placed from cuspid hook to cuspid hook, a physiologic distal force is placed against the maxillary incisors. Periodic slight reduction of the palatal acrylic controls movement to the distal. Simultaneous removal of acrylic can result in rotational movements.