Extraoral forces Intermaxillary tractions

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Extraoral forces Intermaxillary tractions

  1. Extra-oral forces on rings ( F. E. B).

Definition : removable mechanical device which allows intermittent force to be exerted, in an anteroposterior direction, on the first upper molars, without relying on the anterior teeth.

Description : This device includes:

  1. two rings on the upper first molars (or on the second molars, or sometimes on the lower first molars).
  2. A facebow: made up of 2 internal branches which are inserted at the level of the molar tubes and 2 external branches connected to the traction system.
  3. A driving element: latex elastic, or elastic band,
  4. External anchor: cervical elastic band (support on the neck) or traction helmet (support on the skull)

The different types of F.E.B .: they differ according to the type of external anchor used :

  • low traction: the direction of the force is lower than the occlusal plane (cervical support)
  • medium traction: the direction of the force is parallel to the occlusal plane; association of the cervical band and high traction helmet; (Occipital support)
  • high traction: the direction of the force is higher than the occlusal plane; high traction helmet; (parietal support).

The effects of a FEB on braces (upper first molars ) : Orthodontic effects :

At the level of the first molars : three types of movement are possible:

  1. A translational movement.
  2. A version movement:

— mesial or distal coronal version; radicular version; associated coronal and radicular versions.

  1. A vertical movement: egression or ingression.

Orthopedic effects :

  • The maxilla rotates downwards and backwards.
  • The FMA angle shows a slight increase with different FEBs

Indications :

  • molar retraction for correction of a Class II discrepancy;
  • preservation of a mesial drift space;
  • preservation of molar anchorage (fight against anchorage loss).

Contraindication : Posterior DDM.

Time of application : The most favorable period is when the upper premolars are developing, when the germs of the 12-year-old teeth are still high up.

Duration of wear : from 10 hours to 14 hours or more per 24 hours depending on whether you want to achieve simple blocking of the molars or distalization of these teeth.

  1. EXTRAORAL FORCES ON SLOT .

Definition : these are devices using extraoral forces whose action is distributed over the entire set of teeth, using a resin tray covering all the teeth.

The inner arch of the facebow is enclosed in resin or removable and sliding in 2 lateral tubes. It is a device with an orthopedic mode of action , allowing the application of intermittent heavy forces, in anteroposterior direction.

Constitution of FEB on gutters :

  • A resin gutter that covers the palatal, occlusal and vestibular surfaces of all the teeth, particularly at the incisal level, the palate is cleared;
  • The facebow: the internal bow is located at the incisal level. The anchor hook is placed between the first and second premolars, halfway up the roots;
  • high traction helmet.

Mode of action : This is an orthopedic device that tends to distalize the maxillary alveolar zone without precise control of the dental axes. It can be used in stable mixed dentition and sometimes in stable adolescent dentition.

  1. Orthopedic action :
  • recession of the lower part of the maxilla (alveolar bone) and recession of point A.
  1. Action on the teeth :
    • correction of arch relationships in the anteroposterior direction;
    • reduction of incisal overjet with lingual version of the upper incisors.
    • slight distortion of all the teeth in the lateral sectors;

Device port :​

  • the forces exerted can reach 1 kg, their increase must be very gradual;
  • the port must be at least 14 hours per 24 hours:

Indications : In the maxilla:

  • Class II Division 1, without DDM with medium or horizontal growth type.
  • The supporting teeth must be stable, therefore at the stage of stable mixed dentition.

Contraindications :

  • long face;
  • Posterior DDM;
  • if the treatment plan includes extractions.

Benefits :

  • Orthopedic modifications;
  • easy to make;
  • spaced controls;
  • allows extractions to be avoided, if the desired effects are obtained.

Disadvantages :

  • Most often requires a second step in fixed technique;
  • Increases overall treatment time;
  • May cause posterior crowding
  • Psychological impact
  1. The occipito-mental sling :

(See class 3 treatment course)

  1. Delaire ‘s mask :​

(See class 3 treatment course)

INTERMAXILLARY TRACTIONS ( IMT ) .

TIMs are tractions exerted by elastic bands stretched between the two arches, and placed by the patient on a fixed device.

The attachment points are anterior or lateral and vestibular or lingual. The resultant forces are oblique or vertical.

The force can be adjusted depending on the diameter of the elastic and the wearing method (continuous or discontinuous wearing).

However, patient cooperation is crucial to the effectiveness of this device.

The different types of T.I.M. and their mode of action .

  1. Oblique elastics .
    1. Class II elastics :​
      • Attachment points: 36 and 46 (or 37 and 47) and 13 and 23 (or mesial to the canines).
  1. Biomechanical characteristics: the forces exerted have a horizontal and vertical component.
  2. Action on the teeth:
    • Distalization of the maxillary arch and mesialization of the arch

mandibular.

  • egression and mesioversion 36 and 46;
  • vestibulo-version of the lower incisors;
  • slight extrusion of the upper incisors;
  • slight upper molar recession.
  1. Action on the occlusal plane: tilts downwards and backwards. Consequences: the chin lowers and moves back.

Action on the vertical direction: class II elastics increase the DV

  1. Indications: treatment of class II malocclusions;
  2. Contraindications: long face; posterior rotation.
  3. Incidents:
  • slippage caused by stretching of the joint ligaments.
  • pain in the anchor molars or excessive mobility of these teeth.
  1. Class III elastics :​
    • anchor points: 16 and 26 (or 17, 27), and 43 and 33:
  1. Biomechanical characteristics: identical to Class II TIMs.
  2. Action on the teeth:
    • Distalization of the mandibular arch and mesialization of the arch

maxillary.

  • egression and mesioversion of 16 and 26;
  • vestibulo-version of the upper incisors
  • disto-version of 46 and 36;
  • linguoversion and egression of the lower incisors.
  1. Action on the occlusal plane: tilts up and back.
  2. Indication: treatment of certain Angle class III anomalies.
  3. Contraindications: long face; posterior rotation.
  4. Anterior oblique elastics : attachment points 12-32 or 22-42.

– Indication: correction of a deviation of the media.

  1. Vertical elastics :
  2. Anterior vertical elastics: “square” elastics: attachment points: on 2 or 4 upper and lower incisors V or L.
  • Indication: correction of anterior open bites.
  • Contraindication: short upper lip, vertical TIMs leading to worsening of the gummy smile.
  1. Posterior vertical elastics: (crisscross elastics ) :

attachment points : vestibular on one tooth (cuspid teeth) and lingual on the antagonist Example: 16 Lingual – 46 Vestibular.

Indications:

linguoclusion of the upper premolars and molars. (16 L – 46 V). exaggerated vestibuloclusion of the maxillary premolars and molars (16 V – 46 L).

Extraoral forces Intermaxillary tractions

  Untreated cavities can cause painful abscesses.
Untreated cavities can cause painful abscesses.
Dental veneers camouflage imperfections such as stains or spaces.
Misaligned teeth can cause digestive problems.
Dental implants restore chewing function and smile aesthetics.
Fluoride mouthwashes strengthen enamel and prevent cavities.
Decayed baby teeth can affect the health of permanent teeth.
A soft-bristled toothbrush protects enamel and sensitive gums.
 

Extraoral forces Intermaxillary tractionsExtraoral forces Intermaxillary tractions

  1. Extra-oral forces on rings ( F. E. B).

Definition : removable mechanical device which allows intermittent force to be exerted, in an anteroposterior direction, on the first upper molars, without relying on the anterior teeth.

Description : This device includes:

  1. two rings on the upper first molars (or on the second molars, or sometimes on the lower first molars).
  2. A facebow: made up of 2 internal branches which are inserted at the level of the molar tubes and 2 external branches connected to the traction system.
  3. A driving element: latex elastic, or elastic band,
  4. External anchor: cervical elastic band (support on the neck) or traction helmet (support on the skull)

The different types of F.E.B .: they differ according to the type of external anchor used :

  • low traction: the direction of the force is lower than the occlusal plane (cervical support)
  • medium traction: the direction of the force is parallel to the occlusal plane; association of the cervical band and high traction helmet; (Occipital support)
  • high traction: the direction of the force is higher than the occlusal plane; high traction helmet; (parietal support).

The effects of a FEB on braces (upper first molars ) : Orthodontic effects :

At the level of the first molars : three types of movement are possible:

  1. A translational movement.
  2. A version movement:

— mesial or distal coronal version; radicular version; associated coronal and radicular versions.

  1. A vertical movement: egression or ingression.

Orthopedic effects :

  • The maxilla rotates downwards and backwards.
  • The FMA angle shows a slight increase with different FEBs

Indications :

  • molar retraction for correction of a Class II discrepancy;
  • preservation of a mesial drift space;
  • preservation of molar anchorage (fight against anchorage loss).

Contraindication : Posterior DDM.

Time of application : The most favorable period is when the upper premolars are developing, when the germs of the 12-year-old teeth are still high up.

Duration of wear : from 10 hours to 14 hours or more per 24 hours depending on whether you want to achieve simple blocking of the molars or distalization of these teeth.

  1. EXTRAORAL FORCES ON SLOT .

Definition : these are devices using extraoral forces whose action is distributed over the entire set of teeth, using a resin tray covering all the teeth.

The inner arch of the facebow is enclosed in resin or removable and sliding in 2 lateral tubes. It is a device with an orthopedic mode of action , allowing the application of intermittent heavy forces, in anteroposterior direction.

Constitution of FEB on gutters :

  • A resin gutter that covers the palatal, occlusal and vestibular surfaces of all the teeth, particularly at the incisal level, the palate is cleared;
  • The facebow: the internal bow is located at the incisal level. The anchor hook is placed between the first and second premolars, halfway up the roots;
  • high traction helmet.

Mode of action : This is an orthopedic device that tends to distalize the maxillary alveolar zone without precise control of the dental axes. It can be used in stable mixed dentition and sometimes in stable adolescent dentition.

  1. Orthopedic action :
  • recession of the lower part of the maxilla (alveolar bone) and recession of point A.
  1. Action on the teeth :
    • correction of arch relationships in the anteroposterior direction;
    • reduction of incisal overjet with lingual version of the upper incisors.
    • slight distortion of all the teeth in the lateral sectors;

Device port :​

  • the forces exerted can reach 1 kg, their increase must be very gradual;
  • the port must be at least 14 hours per 24 hours:

Indications : In the maxilla:

  • Class II Division 1, without DDM with medium or horizontal growth type.
  • The supporting teeth must be stable, therefore at the stage of stable mixed dentition.

Contraindications :

  • long face;
  • Posterior DDM;
  • if the treatment plan includes extractions.

Benefits :

  • Orthopedic modifications;
  • easy to make;
  • spaced controls;
  • allows extractions to be avoided, if the desired effects are obtained.

Disadvantages :

  • Most often requires a second step in fixed technique;
  • Increases overall treatment time;
  • May cause posterior crowding
  • Psychological impact
  1. The occipito-mental sling :

(See class 3 treatment course)

  1. Delaire ‘s mask :​

(See class 3 treatment course)

INTERMAXILLARY TRACTIONS ( IMT ) .

TIMs are tractions exerted by elastic bands stretched between the two arches, and placed by the patient on a fixed device.

The attachment points are anterior or lateral and vestibular or lingual. The resultant forces are oblique or vertical.

The force can be adjusted depending on the diameter of the elastic and the wearing method (continuous or discontinuous wearing).

However, patient cooperation is crucial to the effectiveness of this device.

The different types of T.I.M. and their mode of action .

  1. Oblique elastics .
    1. Class II elastics :​
      • Attachment points: 36 and 46 (or 37 and 47) and 13 and 23 (or mesial to the canines).
  1. Biomechanical characteristics: the forces exerted have a horizontal and vertical component.
  2. Action on the teeth:
    • Distalization of the maxillary arch and mesialization of the arch

mandibular.

  • egression and mesioversion 36 and 46;
  • vestibulo-version of the lower incisors;
  • slight extrusion of the upper incisors;
  • slight upper molar recession.
  1. Action on the occlusal plane: tilts downwards and backwards. Consequences: the chin lowers and moves back.

Action on the vertical direction: class II elastics increase the DV

  1. Indications: treatment of class II malocclusions;
  2. Contraindications: long face; posterior rotation.
  3. Incidents:
  • slippage caused by stretching of the joint ligaments.
  • pain in the anchor molars or excessive mobility of these teeth.
  1. Class III elastics :​
    • anchor points: 16 and 26 (or 17, 27), and 43 and 33:
  1. Biomechanical characteristics: identical to Class II TIMs.
  2. Action on the teeth:
    • Distalization of the mandibular arch and mesialization of the arch

maxillary.

  • egression and mesioversion of 16 and 26;
  • vestibulo-version of the upper incisors
  • disto-version of 46 and 36;
  • linguoversion and egression of the lower incisors.
  1. Action on the occlusal plane: tilts up and back.
  2. Indication: treatment of certain Angle class III anomalies.
  3. Contraindications: long face; posterior rotation.
  4. Anterior oblique elastics : attachment points 12-32 or 22-42.

– Indication: correction of a deviation of the media.

  1. Vertical elastics :
  2. Anterior vertical elastics: “square” elastics: attachment points: on 2 or 4 upper and lower incisors V or L.
  • Indication: correction of anterior open bites.
  • Contraindication: short upper lip, vertical TIMs leading to worsening of the gummy smile.
  1. Posterior vertical elastics: (crisscross elastics ) :

attachment points : vestibular on one tooth (cuspid teeth) and lingual on the antagonist Example: 16 Lingual – 46 Vestibular.

Indications:

linguoclusion of the upper premolars and molars. (16 L – 46 V). exaggerated vestibuloclusion of the maxillary premolars and molars (16 V – 46 L).

Extraoral forces Intermaxillary tractions

  Untreated cavities can cause painful abscesses.
Untreated cavities can cause painful abscesses.
Dental veneers camouflage imperfections such as stains or spaces.
Misaligned teeth can cause digestive problems.
Dental implants restore chewing function and smile aesthetics.
Fluoride mouthwashes strengthen enamel and prevent cavities.
Decayed baby teeth can affect the health of permanent teeth.
A soft-bristled toothbrush protects enamel and sensitive gums.
 

Extraoral forces Intermaxillary tractions

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