by ·Guan Qing, speaker of modern standardized root canal therapy, original price: 299, special price for limited time: ￥ 279 click the icon to pay attention to our orthodontic mobile appliance, which is an orthodontic device attached to teeth and mucous membrane.
Patients can take it off and wear it by themselves to correct malocclusion.
It is mainly composed of three parts: force adding, retaining and connecting device.
This article mainly talks about the bending of the stressed components.
The force application part includes lip bow, spring, rubber band, spiral device, etc.
The following describes the function and bending method of the force adding member of the common mobile appliance: what is the lip arch? It is the arc arch wire located on the lip side of the crown or alveolar in front of the dental arch on the mobile appliance.
Hyperbolic lip arch is the most commonly used lip arch, which is located on the labial side of the crown of the upper and lower anterior teeth.
It is used to close the space between the anterior teeth, narrow the anterior arch and correct the anterior teeth with lip dislocation.
It is also used to maintain and stabilize the effect after correction.
It can also weld springs or traction hooks and other accessories on the lip arch to correct all kinds of misplaced teeth.
The lip arch can be bent with 0.7mm or 0.8mm diameter stainless steel wire.
Bending method ① first draw the position of the double curvature lip arch with a pencil on the model.
Generally, take a section of stainless steel wire, bend it into a regular arc along the position of the lip arch on the labial surface of the incisor, and align the middle of the steel wire with the midpoint of the dental arch for comparison.
② Mark the junction between the mesial and middle 1 / 3 of the canines on both sides, bend the steel wire from here to the gingiva at an angle of nearly 90 ° to the lip arch, and bend the steel wire to the occlusal side 3 ~ 4mm above the gingival margin to form two straight “U” curves parallel to the long axis of the canines.
The “U” curve should be 1 ~ 1.5mm away from the buccal attached gingiva.
The length and width of the curve depend on the length and width of the canines, and then pass through the buccal and The occlusal abduction space forms a connector to the palatal side and is fixed in the base.
Precautions ① the position and shape of the double lip bow can be changed due to different functions.
If the retention is enhanced, the double lip bow should be bent with stainless steel wire with a diameter of 0.8mm or 0.9mm.
Its horizontal part can be located in more than 1 / 3 of the crown of the anterior teeth or close to the neck of the teeth, and its retention effect is better.
If the dental arch is reduced, the lip arch should be bent with stainless steel wire with a diameter of 0.7mm or 0.8mm, because it is flexible and easy to adjust.
The horizontal part of the lip arch can be located in the middle 1 / 3 or cut 1 / 3 of the anterior crown.
The double curvature of the lip arch should be short and wide, which is convenient for adjusting and gradually reducing the double curvature during force application.
If the dental arch is expanded, for example, when the dental arch is expanded with the expansion spring and split base, the lip arch has a dual role, that is, to enhance retention and generate force.
Therefore, the lip arch should be bent with stainless steel wire with a diameter of 0.8mm, and the double curvature of the lip arch should be long and narrow to enhance retention, and it is also convenient to adjust the double curvature of the lip arch accordingly in the process of expanding the dental arch.
The position of its horizontal part should be kept in the center of the labial surface of the incisor.
② When bending, pay attention to the double curvature, which shall be parallel and symmetrical, smooth and without acute angle.
Hyperbolic tongue spring is used for the correction of palatal lingual misplaced teeth.
It is generally bent with stainless steel wire with a diameter of 0.5 ~ 0.6mm.
The anterior teeth are generally 0.5mm and the posterior teeth are 0.6mm.
Of course, for deciduous teeth, Australian wires of 0.014 and 0.016 inches can also be used to avoid excessive correction force.
A.
Double tongue spring bending; B.
Double curved tongue spring for correction of lingual dislocation tooth bending method ① select a section of steel wire with appropriate specification, clamp one end of the steel wire with pliers in the right hand, stroke out the arc a basically consistent with the curvature of the neck edge of the lingual side of the tooth with the fingers of the left hand, place the free end in the proximal middle of the lingual side of the tooth (if it is a twisted tooth, it is located at the twisted end of the lingual side), compare it on the model, mark a point at the distal edge ridge, and turn the steel wire back to the proximal middle at this point to form the first curve a, The curved arm B should be slightly shorter than the mesial and distal width of the tooth.
② Rotate and bend the steel wire to the distal edge ridge at 0.5mm from the free end of the tongue spring to form the second curve B.
The second curve and the first curve should be in the same plane to form a spring plane.
The corner of the curve is round and blunt, and the distance between the hyperbolas should be reduced as much as possible, so as to increase the adjustable range of the spring.
③ Clamp the spring plane with pliers, and bend the free end of the second curve vertically downward at the position equivalent to the middle point of the first curve, so that it is 90 ° with the spring plane, and the second curve width C is 1 / 2 of the first curve width.
④ Place the hyperbolic tongue spring at the lingual protrusion of the tooth, make the spring plane perpendicular to the long axis of the tooth, and then form a connector shape d along the shape of the mucosal fold on the palatal (lingual) side, so that it is 0.5 ~ 1mm away from the mucosa, and the end is bent into a ring-shaped or hook shaped retainer.
Precautions ① when bending, make sure that the spring plane is perpendicular to the long axis of the tooth and placed at 1 / 3 of the neck edge of the tongue.
Only in this way can the whole tooth body be moved as much as possible.
At the same time, the distance between hyperbolas shall be tightened as much as possible, so as to make force application more convenient.
② When the force is applied, the tightened hyperbola is opened, the hyperbola in the wearing inlet is pressed, and the restoring force of the spring pushes the tooth to the labial side.
③ Hyperbolic tongue spring is usually used for the correction of reverse jaw teeth, but it can also be used to expand the anterior and posterior arch by placing it on the lingual side of different teeth.
The single longitudinal spring mainly uses the correction force generated by adjusting the U-shaped curve to make the dislocated teeth move near and far.
It is often used to correct the canines with the dislocation of the mesial lip and make them shift to the far middle.
It is usually bent with 0.5 ~ 0.6mm stainless steel wire.
Bending method ① remove about 1.0mm of neck plaster in the proximal middle adjacent space of canine..
