Restraint and recidivism

Restraint and recidivism

1- Introduction:

Dentofacial orthopedics continues to evolve, progress is being made in establishing the diagnosis, treatment objectives and developing the treatment plan and above all ensuring therapeutic stability and functional well-being.

So one of the primary objectives of the orthodontist is to ensure the stability of the results obtained in the long term. To achieve this perfection, we must go back to the beginning and look for the causes of the instability in order to counteract them.

I. THE RACEDIVE:

1. Definition :

Post-therapeutic recurrence is the reappearance of an abnormality after its correction, either partially or totally, immediately after retention or in the long term.

Restraint and recidivism

2. The etiologies of recurrence :

They are multiple and can be classified into: *Genetic factors.

*Acquired factors.

*Iatrogenic therapeutic factors.

*Post-therapeutic factors.

*Human factors

2.1 Genetic factors :

By knowing this factor, which is not or hardly modifiable, we can at least choose a treatment which adapts to the genetic conditions;

* Growth with its direction and intensity requires the practitioner to direct his therapy in the same direction as the latter in order to avoid recurrence, therefore growth prediction is important to determine and avoid so-called “unfavorable” growth responsible for recurrence.

*The muscular factor: muscular characteristics such as length, tone, thickness are genetically determined and must be taken into consideration during diagnosis (etiological diagnosis) in order to choose the appropriate treatments to avoid recurrence.

Example: – The persistence of labial hypotonicity promotes the recurrence of pro-alveolus.

-The persistence of macroglossia promotes the recurrence of proalveoli and open bites.

2.2 Acquired functional factors :

The tongue, whether at rest or during orofacial functions, plays a vital role thanks to its supports and motor skills.

*Swallowing: incorrect lingual supports during atypical swallowing, as well as the contraction of the facial muscles, induce an imbalance in the Château dental corridor and promote the recurrence of gaps, proalveolus, latero-deviations, etc.

This is why rehabilitation of this function is essential to avoid recurrence.

*Mouth breathing: it influences not only the lingual posture and the development of the dental arches, but also maxillary growth, the persistence of mouth breathing leads to the recurrence of open bite, gaping, maxillary endognathia, etc.

*Incorrect phonation: inadequate lingual supports that are not corrected are responsible for relapse. Lateral interposition of the tongue in the articulation of the: SJCH promotes relapse of anterior overbite and posterior infra clusia.

* Para-functions: such as:

* Thumb sucking which causes recurrence of open bite and superior pro-alveolus, inferior retro-alveolus.

*Lip sucking: persistence of upper lip sucking leads to recurrence of upper retro-alveoli and lower pro-alveoli.

2.3 Human factors :

This factor targets two essential elements: the patient’s age and their cooperation.

*Age directly related to the growth and periodontium of the patient; the possibilities of relapse increase depending on whether the growth is at its peak, before or after, whether it is finished or not, this is why early treatment is preferred in cl II and late in cl III.

The periodontium of the child is in perpetual tissue remodeling, hence the possibility of reappearance of congestion after treatment, on the other hand the bone is denser; the ligaments are not very compressible in adults, preventing the tooth from moving again.

*Cooperation is based on the wearing of restraint devices, as well as the effort made by the patient in suppressing parafunctions and maintaining myotherapy exercises.

2.4 Iatrogenic therapeutic factors : may be the result of:

-Incorrect diagnosis or neglect of etiological diagnosis.

-A poor choice of treatment plan poorly adapted to growth.

– Poor treatment finish.

– Poorly adapted support.

– Poor choice of treatment timing.

– Poor therapeutic technique.

2.5 Post-therapeutic factors :

Some treatments, especially those carried out early, are likely to recur due to changes in the terrain such as:

*The eruption of new teeth, especially wisdom teeth, which play a part in the recurrence of lower crowding.

*Late growth of the maxillary bases, mainly of the mandible, which promotes the recurrence of class III and overbites.

*The phenomena of aging.

3. How to prevent recurrence ?

We have become accustomed to thinking directly about containment to prevent recurrence, but in reality it comes last, to summarize it is enough to review all the etiological factors, to counteract them or avoid them to ensure the stability of the results.

*Growth forecast: it allows to assess the mandibular rotation, the quantity of growth and its intensity.

*Achievement of end of treatment criteria (occlusal-aesthetic-functional).

*Overcorrection.

*Other preventions stripping – post orthodontic occlusal equilibration – coronoplasty – supracrestal fibrotomy)

*Contention device.

Restraint and recidivism

II.CONTENT:

1. Definition :

It is a process intended to maintain or perfect the results obtained, in order to avoid the occurrence of relapse, it begins at the end of the active treatment when the orthodontist judges that he has achieved his objectives.

2. The aims of restraint :

-The main goal is the prevention of recurrence.

-Stabilization of teeth during tissue reorganization.

-Promote the establishment of good occlusion.

-Counteract the effects of residual growth going in the wrong direction of the results obtained.

-Maintain skeletal offset correction.

-Maintain favorable conditions for the correct execution of the various functions.

3. When should you use or not use a retainer ?

Some authors disagree on the usefulness of restraint, but this remains relative to certain anomalies, because there is no longer any question of doubting the essential role of restraint.

*It is essential to place a restraint device in cases treated by:

-Leveling with expansion.

-Large amplitude space closure.

-Correction of severe rotations or malpositions.

-After correction of hereditary cl III.

-After treatment of cleft lip and palate.

-Early treatment before the end of residual growth.

*Among the cases where we can do without restraint (natural restraint):

-After correction of an incisal crossbite with good coverage.

-After correction of a posterior crossbite with good intercuspidation is.

-Case of class II which has been treated by propulsion and where mandibular growth is not yet complete, it will serve as a means of retention.

-Case of cl II which was treated by maxillary FEB, if the growth is finished, there will be no recurrence.

-Case of repositioning of an included or retained tooth.

-Case of a DDM by microdontia after treatment and fitting of a prosthesis.

4- Moment of restraint :

Although authors differ on the timing of retention, the time interval between removal of active treatment and placement of retention should not exceed one week for all authors.

-For Burston a week later to observe stability.

-For Reitan who showed that the recurrence movement is maximal after 2 hours of removal of the active device, during the 5 hours which follow it is necessary to place the restraint.

Restraint and recidivism

– Julien Philippe is in favor of immediate restraint.

5. Duration of restraint :

The decision on the duration depends on several factors: the age of the patient, the stage of growth and its direction, the facial typology, the degree of complexity of the anomaly treated, and the type of retention.

The retention can be prolonged, semi-permanent or permanent worn for life, it must continue until the surrounding tissues and oral functions are adapted to the new dental position and the new shape and position of the arches.

– For removable support, the majority of authors recommend wearing it for 3 months day and night, then 9 months only at night, or 1 year in total.

This port can be longer, but then discontinuous, in cases of significant initial rotations and in cases of dento-maxillary disharmony treated without extractions,

Where the second molars are not developed at the start of retention. It can also be maintained in certain patients during growth (hyperdivergent, deep-bite,

class III), showing a persistent functional problem, or whose wisdom teeth are retained.

The duration of retention also increases when there have been significant and rapid movements. Long treatments are generally more stable.

Retention for several years, or even for life, is necessary for patients, especially adults, with fragile periodontium.

6- Types of restraint :

6.1 – Active : it is an integral part of the processing, its purpose is:

-Closure of residual spaces due to molar rings.

-Correction of minor anomalies not treated during active treatment.

-Maintaining the correction of the anteroposterior shift.

6.2. Passive : this is the most frequently used, it does not deliver mechanical action, it only maintains the results obtained.

6.3. Fixed : it is generally glued to the lingual surface of the teeth, always in place and will not be removed.

6.4 Removable : the risk of recurrence is significant with this type of device .

7. The main restraint devices :

7.1 Removable single maxillary :

*Hawley plate: this is the most used. Semi-passive, it can close small diastemas. With little occlusal interference, it also promotes the occlusion of the incisors and canines. It is not very thick.

* Plate with Vienna bracket: this active retention plate (by the tension of a vestibular elastic) is indicated in the event of persistent significant incisor diastemas.

* Removable plates with accessories (spring, screws, etc.): these are active retainers for minor single correction.

* Plate with inclined propulsion plane: this is a restraint used in classes II.

* Eschler plate for class III: it is a maxillary plate with a vestibular band on the lower incisors.

* Nocturnal lingual envelope (NLE): it contains the tongue but does not ensure the maintenance of alignment.

*Sved plate: it covers the edge of the maxillary incisors and provides a stop for the mandibular incisors. It is indicated to contain the correction of an initial overbite.

*Gutters

* Retainer: device with little palatal grip; it holds the teeth more firmly but not enough to contain strong rotation corrections. Its occlusal hooks can interfere with occlusion.

*Thermoformed splint: space-saving, transparent, it fixes the tooth in all three directions of space. However, it leaves little possibility of natural wedging, interferes with occlusion and can cause gaps if worn for a long time. Small movements are possible, in version, by inserting a thin thickness of composite.

7.2 Removable bi-maxillary :

*Tooth positioner (repositioning splint): prefabricated splint: made of soft and transparent plastic, adapted to teeth of usual shape and proportion and to classic orthodontic solutions (with or without extractions), they exist in different sizes, always according to the same arch shape and are not individualizable. Free in the mouth, this splint is designed to correct a slight punctate defect but poorly maintains the correction of rotations.

*Activators: help consolidate and improve maxillomandibular relationships in the antero-posterior and vertical directions.

*Intermaxillary traction (TMA) placed on removable plates or retainers, allow the correction of sagittal and frontal shifts to be stabilized.

7.3 Single maxillary fixed :

* Wire glued to two teeth: left and right canines. This round section wire (.024), polished, has a good longevity. It maintains the intercanine distance well but poorly ensures the contention of incisor derotations or their lingual-version. It leaves an incisor occlusal adaptation possible, in particular vertical.

* Wire glued to six teeth: canines and incisors. Most often made of braided round wire (.0175 and .0215), this device glued to the occlusal 1/3 of the tooth better controls the correction of rotations. Sometimes integrated into incisor wedges, in the maxilla, for the contention of overbites, it can also be more extensive to contain the closure of an extraction space or in the presence of a fragile periodontium (in adults in particular). The detachment of a tooth can go unnoticed.

* Cast-glued splints.

$C:\Users\SORAYA\Pictures\4.jpg$ Transparent thermoformed maxillary retainer.