Removable orthodontic therapy
Introduction :
Removable orthodontic therapy: In orthodontics, the concepts of treatment success and failure are still poorly defined.
So much so that no treatment model has been the subject of a consensus, thus acquiring the approval of the entire profession.
However, the advantages of removable therapy are undeniable. It is nevertheless necessary to have well-defined objectives.
Definition
Removable according to the French Academy : Which can be placed or moved at will
Removable appliances allow, particularly in mixed dentition or in certain cases in adults, the correction of certain malocclusions or dental malpositions.
These devices were used with predilection in Europe until the 1960s.
And despite the shadow cast by fixed technique, their use remains incontestable in terms of containment.
Historical
HUNTER , 1771 , was the first to use an inclined plane
Fox , in 1803 a disciple of Hunter, had the idea of interposing ivory squares to allow the articulation jump
Removable plates , made of metal, ivory, then vulcanite, were developed as soon as practitioners had faithful casts, from 1840
DESCRIPTIVE STUDY
Palatal plates consist of three major parts: the base, the retention elements and the active elements.
1- The base
The material used for its production is acrylic resin. This resin, generally used in self-polymerizing form, comes in the form of a liquid and a powder to be mixed. Sometimes, this resin comes in the form of plates; in this case, its implementation requires a device which is the thermoformer.
This base, 2 to 3 mm thick, covers all or part of the support surface. Modifications of the shape of this base are used for therapeutic purposes.
2-Retention hooks (passive)
The Simple Hook: this is a passive retention hook made with stainless steel wire 0.7 – 0.8 mm in diameter.
Description and making
- ·It has a part which rests on the vestibular surface of the tooth (generally the molar or premolar).
- ·The end of the wire ends in a loop, this rests at the level of the mesial or distal 1/3 below the line of the largest contour in the undercut area which allows the hook to acquire its retention quality.
- The second part of the wire passes through the interdental space to end in the palatine region with a 90° retention parallel to the palatine mucosa
Cavalier Hook
It is a passive retention hook made with 0.7 mm diameter steel wire.
Description :
- It is bent at 90° so as to fit between the teeth just below the contact point which serves as retention.
- It is performed at the level of both arches, most often in the mandible in cases where the teeth are tight.
- These hooks can also be used in raised gutters.
Adams Hook
It is a passive retention hook on molar or premolar shaped with 0.7 mm diameter steel wire.
Description
Includes a horizontal part located halfway between the coronal height and laterally two sagittal points which are applied in the mesial and distal retention zone of the vestibular face.
The free ends of the sagittal tips folded in the triturating direction are adjusted in the interdental grooves to end in a 90° retention.
Benefits
- No special pliers are needed to shape this hook
- Little contact with the enamel, less risk of decay, it is also performed on a temporary tooth and it can be preformed.
The essential characteristics of the Adams hook
- The sagittal tips must not touch adjacent teeth at any time.
- The horizontal part between the sagittal points should be located halfway between the vestibular surface of the tooth and the adjacent soft tissue to avoid any friction with either. If this part is too close to the gum it will cause irritation and pain when the hook is tightened.
- The free elements of the hook should pass under the contact points as close to the teeth and adjusted in the lingual embrasures and distant from the palatal or lingual mucosa.
Hook adjustment
- Bend the sagittal tips inwards.
- Overtightening of the hook should be avoided as it is not necessary.
Schwartz Hook
- It is a means of vestibular anchoring, which ensures the stability of the plate.
- It is based on 02 or 03 aligned teeth, it has a contact point thanks to 01 or 02 lanceolate teeth.
- It is made with 0.7 mm diameter stainless steel wire using Schwartz pliers.
Removable orthodontic therapy
Qualities:
- The Schwartz break is an excellent means of anchoring: great stability of the plate.
- Can be performed in mixed or permanent dentition provided that the teeth used for support are in a continuous line and even if they are erupting.
- Does not damage soft tissues.
Disadvantages:
- The lanceolate retains food debris (if there is no rigorous hygiene).
- It tends to spread apart the teeth between which it is inserted.
- The rupture is easily deformed.
3-Active hooks
Vestibular Arch
Also called a vestibular headband, it is made with 0.7mm diameter stainless steel wire.
Description :
It includes a central, horizontal band and 02 “U” shaped loops opposite the canines ending with 02 palatal arms or retention loops.
Activation:
It is done every 3 weeks by tightening the curls in a “U” shape with pliers.
Diastema Reducers
It is a cantilever type hook, located on the palatal side made with 0.6 mm diameter stainless steel wire.
Description :
- Made up of 02 hooks, each of which includes an active arm, a coil and a retention arm.
- Used at the level of the central and lateral incisors to reduce an existing diastema between 02 central incisors.
- Used to distalize or mesialize an incisor.
Activation:
It is done by bringing the 02 active arms of the two hooks towards each other.
Omega Hook
It is an active hook made with 0.6mm diameter stainless steel wire.
Removable orthodontic therapy
Description
It is a palatal hook with a slightly rounded anterior part in contact with the palatal or lingual face of the incisors to be vestibluer. This part is followed by two right and left coils placed on either side mesial and distal to the retroincisive papilla which ends with retention arms and their end two retention loops.
Activation
It is done by pulling forward the part in contact with the palatal or lingual surface of the incisors.
Canine Retractor
It is a hook that is used to distally tilt the canine, it is made with stainless steel wire (0.7 – 0.6 mm).
Description :
It is vestibular in location, it includes a mesial arm and a distal arm which are joined by a coil, the end of the mesial arm ends with a bend.
The distal arm is extended lingually by a retention loop.
Serpentine Hook
It is a cantilever type hook located on the palatal face and made with 0.6mm diameter stainless steel wire.
Description :
It consists of an active arm and a retention arm which ends with a retention loop.
The active arm has steps which give it the appearance of a spring and which gives great elasticity, it concerns the incisors, it is used to vestibulate an incisor in palatal version.
Activation:
It is done by opening the steps of the Serpentine, and having the hook in contact with the palatal face of the tooth.
The jack
It is a prefabricated mechanical device which rests on the edges of a split plate.
Depending on the direction of activation, it will either bring the edges of this plate closer together or further apart. This device allows movements to be made in the transverse direction and, incidentally, in the anteroposterior direction.
Removable orthodontic therapy
The middle cylinders:
The resin plate is melted longitudinally in its middle and the jack is placed perpendicular to this slot, the activation of this jack determines for some a vestibulo version of the lateral sectors, thus correcting an endoalveolus.
It should also be noted that the correction of the inferior endoalveolus.
The side cylinders:
They are used to distalize the lateral sectors. Distalization can be unilateral or bilateral, the slit(s), transverse, are located mesially to the sectors to be distalized. These jacks can be associated with a median jack.
4-Movements made with removable orthodontic appliances
Vestibulolingual movement:
- If the incisor(s) are in a palato position, it is necessary to ensure that the gearing does not prevent the articulation jump, otherwise it is necessary to place an elevation:
- To vestibulate an incisor, a serpentine type spring can be used.
- To vestibulate 2 or more incisors, the Schwatz “omega” hook or an anteroposterior action jack
- For the vestibulo-version we use a vestibular arch
Mesiodistal movement
For the incisors we use the distalizers or the mesializers for the canines we use the canine retractor
The expansion:
- Aims to increase the width of the arch, indicated in endoalveoli with post cross bite. This expansion is mainly carried out in the maxilla with a jack
Rotations:
- correction is difficult and can only be achieved for a flat tooth “incisor” for this we use a vestibular arch and a “torque force” pusher
Egression movement:
- Egression is achieved by unilateral molar elevation to correct the incisor overbite.
- Aggression movement impossible to obtain it
5-Passive plates
Space Maintainer
The palatal plate is indicated in cases of premature loss of deciduous teeth, particularly the 2nd temporary molar.
It is intended to prevent the eruption of antagonist teeth and the version of adjacent teeth.
In cases of long-term absence of several temporary teeth, she will be able to wear teeth, thus creating a real infant prosthesis.
Hawley’s passive plate:
This is the most common standard restraint made for:
- maintain the position of the incisors and canines
- preserve the vestibulolingual reports obtained at the end of treatment.
The tooth positioner:
It is a bimaxillary splint that covers all of the upper and lower teeth. It is made of soft resin, rubber or transparent silicone. The elasticity of these materials gives it ideal flexibility for retention.
- Indications:
- closing of spaces left by the thickness of the molar bands
- coordination of arcades
- improvement of low axial inclinations
- perfect the cusp mesh
- maintenance and stabilization of the results obtained
The port of the removable device.
Removable devices must be worn day and night, outside of meals.
A properly worn device should fit naturally and effortlessly.
Clean three times a day with a nail brush and Marseille soap; leave the appliance in a detergent product during the evening meal.
advise, during the first 48 hours, speaking exercises out loud, emphasizing CH, S and F.
Control :
- activation every three weeks
- a spring should not be reactivated while it is still active
- very wide clearance of teeth during development
- readjustment of misaligned retention elements
Benefits of removable orthodontic therapy
Removable orthodontic therapy in all its splendor:
- treats, corrects or simply improves evolving dysmorphias
- prevents worsening of skeletal and dental abnormalities
- at the same time prevents recurrence .
Removable orthodontic therapy
Limitations & Contraindications
Related to the practitioner
It may be the practitioner’s inability to know or to be able to
- on the one hand, properly carry out the equipment
- and on the other hand to make a good diagnosis.
Related to the device itself
Removable plates are so-called simple devices because:
Only version movements are allowed, as opposed to multi-ring techniques
The point of application of the force is virtually punctate, unlike brackets for which it is a support surface. The force is therefore poorly controlled
Patient related
Motivation and cooperation are the key to successful treatment. If the patient is not motivated, it is a limitation to the treatment, as is the inability to maintain good hygiene.
Conclusion
To believe that there could be a treatment method as a panacea for our problems would be rather utopian; however, removable devices whose indication has been well established and whose production and adjustments are well mastered can satisfy a good number of our expectations.
However, it is important to know how to ask this type of device for what it is capable of doing, while keeping in mind that the key to success undoubtedly remains the patient’s motivation .
Good oral hygiene is essential to prevent cavities and gum disease.
Regular scaling at the dentist helps remove plaque and maintain a healthy mouth.
Dental implant placement is a long-term solution to replace a missing tooth.
Dental X-rays help diagnose problems that are invisible to the naked eye, such as tooth decay.
The dentist uses local anesthesia to minimize pain during dental treatment.
Removable orthodontic therapy