Vertical Problems

21
Vertical Problems

21.1 Open Bite

In order to solve an open bite, we need to consider the cause of the open bite, which might be transversal, sagittal or vertical.

Photo depicts vertical cause, excess posterior facial height

Fig. 21.1 Vertical cause, excess posterior facial height.

Photo depicts dentoalveolar cause (protrusion)

Fig. 21.2 Dentoalveolar cause (protrusion).

Photo depicts transversal cause, lingual torque of posterior teeth

Fig. 21.3 Transversal cause, lingual torque of posterior teeth.

With that in mind, key to correcting an open bite are:

  • The amount of posterior expansion which leads to anterior bite closure
  • The capacity of tipping to lingual upper and lower incisors, extruding them relatively

Schematic illustration of the amount of lingual tipping of upper and lower incisors helps to solve an anterior crossbite by relative extrusion and is a key success factor

Fig. 21.4 The amount of lingual tipping of upper and lower incisors helps to solve an anterior crossbite by relative extrusion and is a key success factor.

Factors Determining How to Resolve an Open Bite

Smile Analysis

If there is a gummy smile, the open bite will need to be corrected by posterior intrusion. However, if there is a low smile, it will be possible to extrude upper incisors to correct the open bite.

Photo depicts gummy smile

Fig. 21.5 Gummy smile.

Photo depicts low smile, short display

Fig. 21.6 Low smile, short display.

Patient Biotype

Extruding posterior teeth will rotate the mandible and increase anterior facial height, which might be beneficial or not for patient aesthetics.

Schematic illustration of the facial lower third determines whether to intrude or not to intrude posterior teeth

Fig. 21.7 The facial lower third determines whether to intrude or not to intrude posterior teeth.

Posterior Anchorage Analysis
Schematic illustration of anchorage attachments

Fig. 21.8 Anchorage attachments.

A strong posterior anchorage is needed for effective extrusion of the upper incisors. This anchorage, will be provided by.

  • Not moving the posterior lateral zone during the anterior extrusion
  • Horizontal 5mm attachments on 4s/6s
  • Four lingual attachments on upper incisors during expansion to increase anchorage
  • Optimized attachments or conventional vertical in canines

Anterior Open Bite Anchorage

Although the reciprocal force of the extrusion of the incisor, which in the intrusion of the molars is favourable for the correction of an open bite, attachments are required for the anterior teeth that have to be extruded.

Nevertheless, in the posterior zone, attachments will have a the function of controlling the posterior molar torque during the expansion to prevent the labial cuspids of the molar tipping to labial, which could increase the open bite during the correction.

Requirements for the Technician

Photo depicts chewies or fitters are good for minor open bite cases

Fig. 21.9 Chewies or fitters are good for minor open bite cases.

  • Start the correction as soon as possible by transversal development of both upper and lower arches: this will provide space for the retrusion of the incisors (relative extrusion)
  • During the expansion, it is advisable to use attachments to the lingual surface of the incisors to increase anterior anchorage
  • Postpone absolute extrusion till the end: do not move molars and extrude the upper incisors maintaining torque, remove horizontal bevelled to gingival attachments in lingual and exchange them for optimized extrusion attachments by labial (ask for a reciprocal movement of anterior extrusion and posterior intrusion)
  • Minor cases might benefit from ‘Chewies’
  • Temporary anchorage devices (TADs) should be used to intrude posterior zone (in cases of gummy smile) or when the open bite has a skeletal pattern
Photos depict miniscrews used for absolute posterior intrusion greater than 3 mm, by labial and lingual, and mesial to first molars, enabling the patient to wear an elastic over the aligner

Fig. 21.10 Miniscrews used for absolute posterior intrusion greater than 3 mm, by labial and lingual, and mesial to first molars, enabling the patient to wear an elastic over the aligner.

Anterior Open Bite Biomechanics

Relative Extrusion of Incisors

Relative extrusion can be obtained after expansion if the space opened by the expansion is used to retrocline the incisors:

  • Expansion changing posterior torque + simultaneous incisor retraction + Class II elastics to assist incisors retraction
  • Reciprocal movement of posterior intrusion 0.5mm + anterior extrusion at the end of treatment
  • AT optimized for upper incisors extrusion
    • Anchorage attachments UA4/5
    • Optimized/vertical attachment in canines
Photos depict anterior open bite biomechanics.

Fig. 21.11 Open bite requires careful biomechanics planning.

Pure Extrusion of Incisors using Multi‐tooth Optimized Extrusive Attachments
  • The clinician must examine the smile carefully before deciding if upper incisor extrusion is adequate.
Schematic illustration of optimized anterior extrusion is mostly predictable if it is planned at the end of the treatment with posterior sectors unmovable at that time

Fig. 21.12 Optimized anterior extrusion is mostly predictable if it is planned at the end of the treatment with posterior sectors unmovable at that time.

  • Posterior intrusion of maxillary and mandibular teeth with consequent upward and forward mandibular closure (anticlockwise rotation of the mandible). This is visualized in the ClinCheck as a virtual jump
Schematic illustration of posterior intrusion will have saggital effects as a result of mandibular rotation

Fig. 21.13 Posterior intrusion will have saggital effects as a result of mandibular rotation.

Open Bite Prescription

  • Easy: Less than 2.5 mm is very predictable (better if we do not need posterior intrusion)
  • Moderate: 2.5 mm with less than 1 mm of posterior intrusion
  • Complex: more than 2.5 mm (auxiliary techniques needed)
Schematic illustration of we have to face predictability of vertical movements in order to know whether to plan auxiliary techniques or not

Fig. 21.14 We have to face predictability of vertical movements in order to know whether to plan auxiliary techniques or not.

Question 6 of the Prescription Form

How do we want to correct the open bite:

  • Only by anterior extrusion
  • By anterior extrusion and posterior intrusion
  • Other like surgery (fill special instructions)

Specific Features of an Open Bite

Anterior extrusion:

Schematic illustration of single optimized attachment for extrusion

Fig. 21.15 Single optimized attachment for extrusion.

  • Optimized extrusion AT (single tooth more 0.5 mm)
  • Automatically placed by the software for extrusion
  • Only on upper and lower anterior incisors
  • Threshold is 0.5mm
  • Crown size and anatomy will determine placement

Multitooth optimized extrusion attachments (to extrude all the upper incisors as a unit):

  • They will override any other attachment on these teeth
  • Placed at the same time
  • Automatically placed by the software for extrusion
  • Threshold is 0.5mm
Schematic illustration of optimized anterior extrusion is mostly predictable if it is planned at the end of the treatment with posterior sectors unmovable at that time

Fig. 21.16 Optimized anterior extrusion is mostly predictable if it is planned at the end of the treatment with posterior sectors unmovable at that time.

Predictability of the Open Bite Treatment

The predictability of treatment will be high when:

  • Anterior open bite is dental, not skeletal
  • Incisor is proclined at the beginning and can be retroclined, generating a relative extrusion
  • The transversal development of arches is possible, as the expansion of narrow arches will provide of space to retrocline the incisors
  • Open bite can be solved just by anterior extrusion of less than 2.5 mm without need for intrusion of the posterior molars
Schematic illustration of posterior open bite is a good overcorrection in this case

Fig. 21.17 Posterior open bite is a good overcorrection in this case.

Overcorrection

A request for overcorrection could consist of finishing the occlusion with a small gap between the molars or to end up with heavy occlusal contacts, to obtain an overbite of at least 2 mm at the end of treatment.

Occlusal Attachments

Occlusal attachments might be useful for increasing posterior intrusion forces, as anterior precision bite ramps. They can be filled with composite and then the proper attachments bonded to molar occlusal surfaces or can be left empty, assuming that the plastic will be occluded with more pressure than with a regular aligner.

Schematic illustration of unpredictable posterior intrusion is assisted by upper and lower occlusal attachments that increase bite forces on posterior sector

Fig. 21.18 Unpredictable posterior intrusion is assisted by upper and lower occlusal attachments that increase bite forces on posterior sector.

21.1.1 Open Bite: Transversal and Sagittal Cause

Diagnosis

A 31‐year‐old patient with normodivergent skeletal class I presented with narrow arches with posterior gummy smile and mild crowding.

Treatment Plan

  • Correcting the anterior open bite by retroclining the maxillary and mandibular incisors
  • Maxillary anterior extrusion and posterior intrusion was also requested at the end of the treatment
  • Provide space for retroinclining the incisors, with an expansion that would be performed from the beginning
Photo depicts open bite solved with LITE treatment

Fig. 21.19 Open bite solved with LITE treatment.

Photos depict initial extraoral and intraoral views

Fig. 21.20 Initial extraoral and intraoral views.

Schematic illustration of initial occlusal contact

Fig. 21.21 Initial occlusal contact.

Photos depict initial panoramic X-ray, teleradiograph and cephalometry

Fig. 21.22 Initial panoramic X‐ray, teleradiograph and cephalometry.

Requirements for the Technician

Apply expansion to both arches, perform interproximal reduction (IPR) to correct incisor protrusion and reduce the overjet.

  • Not move molars to use them as anchorage as it is going to be corrected using LITE treatment.
  • Multitooth anterior extrusive attachments to be placed automatically by the software on the maxillary incisors.
  • In the lower arch, IPR to be performed in order to allow for correction of incisor protrusion and alignment without further proclination of the lower incisors.
  • A 0.5 mm of posterior intrusion programmed during the incisors extrusion as a reciprocal movement.
Schematic illustration of initial upper and lower ClinCheck views

Fig. 21.23 Initial upper and lower ClinCheck views.

Schematic illustration of initial right and left ClinCheck views

Fig. 21.24 Initial right and left ClinCheck views.

Schematic illustration of interproximal reduction necessary for relative extrusion of upper and lower incisors

Fig. 21.25 Interproximal reduction necessary for relative extrusion of upper and lower incisors.

Treatment Summary

  • The case was completed in 14 months
  • The initial case had 14 aligners which were changed on a 2‐week interval protocol; after that the patient wore a set of another 14 additional aligners
  • The patient used elastics with a class II and vertical pattern for night use during the treatment
  • The smile improved considerably as a result of the expansion
  • The upper occlusal plane was levelled
  • At the end of the treatment the patient had a bleaching and composite veneer in 12
Photos depict initial intraoral views (upper) and views before refinement (lower)

Fig. 21.26 Initial intraoral views (upper) and views before refinement (lower).

Photos depict final intraoral views

Fig. 21.27 Final intraoral views.

Photos depict initial (left) and final occlusal (right)

Fig. 21.28 Initial (left) and final occlusal (right).

Photos depict initial and final smile

Fig. 21.29 Initial and final smile.

Photos depict final panoramic and lateral X-rays

Fig. 21.30 Final panoramic and lateral X‐rays.

21.1.2 Open Bite: Transversal, Sagittal and Vertical Cause

Photo depicts an initial intraoral view

Fig. 21.31 Initial intraoral view.

Diagnosis

A 62‐year‐old patient with a hyperdivergent skeletal class II pattern presented with an open bite with transversal, sagittal and vertical problems. She had maxillo‐mandibular protrusion, labial incompetence, centred upper midline, constricted arches and dental crowns in 11 and 21.

Treatment Plan

  • Expansion, sequential distalization, IPR (to increase the retraction of incisors and the relative extrusion) and simultaneous incisors retrusion
  • In order to solve the patient problem, analyse the malocclusion in the different planes of space:
    • transversal: expansion with control of the torque of the premolars and molars
    • sagittal: correct class II and overjet by sequential distalization (for that purpose, the dental bridge needed to be removed in the lower arch)
    • vertical: close open bite by relative and absolute incisor extrusion
Photos depict initial extraoral and intraoral views

Fig. 21.32 Initial extraoral and intraoral views.

Photo depicts a panoramic X-ray

Fig. 21.33 Panoramic X‐ray.

Photos depict a teleradiograph: proclination of upper and lower incisors, narrow symphysis

Fig. 21.34 Teleradiograph: proclination of upper and lower incisors, narrow symphysis.

Requirements for the Technician

  • Provide expansion to the arches by changing torque and applying labial crown torque to premolar and molars of the upper and lower arches.
  • IPR and simultaneous incisors retraction to create relative extrusion of the incisors.
  • Lingual attachments bevelled to gingival on the upper incisors (HBG 3 mm), in order to have anterior anchorage during the expansion.
  • Simultaneously to the expansion, make sequential distalization of the upper arch to correct the dental class II.

Schematic illustration of initial upper and lower ClinCheck views

Fig. 21.35 Initial upper and lower ClinCheck views.

Schematic illustration of interproximal reduction to create relative extrusion of incisors

Fig. 21.36 Interproximal reduction to create relative extrusion of incisors.

Resolving the Transversal Problem

Maxilla:

  • Expansion by change of lateral torque (tipping teeth to labial without moving the root apex) + simultaneous mesial‐out rotation of U6 + IPR
  • AT Horizontal 5 mm U4/6
  • AT optimized U3
  • AT HBG 3 mm palatal of upper incisors (prevent upper incisors intrusion during expansion)

Mandible:

  • Expansion + lower sequential distalization + IPR
Schematic illustration of palatal attachments prevent upper incisors from intrusion during expansion

Fig. 21.37 Palatal attachments prevent upper incisors from intrusion during expansion.

Resolving the Sagittal Problem

  • IPR + class II elastics (4.5 oz)
  • Start with elastics as soon as transverse development is appropriate
  • Upright lower incisors (no proclination)
  • Lower and upper distalization
  • Final overjet on ClinCheck should be 1.5 mm
  • Use class II triangular elastics for sagittal and vertical canine movement
Schematic illustration of initial right and left intraoral ClinCheck views

Fig. 21.38 Initial right and left intraoral ClinCheck views.

Photo depicts triangular elastics in class II. The technician was required to extrude upper incisors at the same time as intruding the molar 0.5 mm posterior during the sequential upper distalization

Fig. 21.39 Triangular elastics in class II. The technician was required to extrude upper incisors at the same time as intruding the molar 0.5 mm posterior during the sequential upper distalization.

Resolving the Vertical Problem

Before starting anterior extrusion:

  • Eliminate palatal attachments on upper incisors
  • Use optimized extrusion attachments on upper incisors
  • Plan upper extrusion at the same time as posterior intrusion (0.5 mm)
Schematic illustration of reciprocal movement of anterior extrusion and posterior intrusion

Fig. 21.40 reciprocal movement of anterior extrusion and posterior intrusion.

Schematic illustration of sequential distalization.

Fig. 21.41 Sequential distalization.

Treatment Summary

  • The treatment was completed in 23 months
  • For the first set of aligners the initial case had 40 aligners which were changed on a 2‐week protocol, and a set of additional aligners which were changed on a 10‐day protocol
  • The patient used elastics with a class II and vertical pattern for night use during the treatment to guide the canines to a final class I relationship
  • The open bite was closed without increasing the gummy smile of the patient
  • The patient is now wearing for her aesthetic veneers on the anterior incisors for further improvement of her smile
Photos depict initial (upper) and final (lower) views.

Fig. 21.42 Initial (upper) and final (lower) views.

Photos depict initial (left) and final occlusal (right).

Fig. 21.43 Initial (left) and final occlusal (right).

Photos depict initial and final smiles and overjet.

Fig. 21.44 Initial and final smiles and overjet.

Photos depict final panoramic and lateral X-rays.

Fig. 21.45 Final panoramic and lateral X‐rays.

21.1.3 Open Bite: Vertical Cause Treated with TADs

Photo depicts the initial intraoral view.

Fig. 21.46 Initial intraoral view.

Diagnosis

A 60‐year‐old diabetic patient presented with an open bite with sagittal and vertical problem. They had hyperdivergent skeletal class III pattern with maxillo‐mandibular protrusion, labial incompetence, right‐side deviation of upper midline and missing 13 and 36.

Treatment Plan

  • Close the open bite by expansion and simultaneous distalization and intrusion of molars in order not to create a gummy anterior smile
  • Open a space for the missing 13
  • Centre both midlines
    • sagittal: correct open bite and open space for missing 13 by simultaneous distalization using TADs in the tuberosity and simultaneous distalization in retromolar zone
    • vertical: close open bite by relative incisor extrusion and by intrusion of upper and lower molars using TADs
Photos depict initial extraoral and intraoral views.

Fig. 21.47 Initial extraoral and intraoral views.

Photos depict goal of treatment: close open bite by upper and lower distalization and relative extrusion of upper incisors.

Fig. 21.48 Goal of treatment: close open bite by upper and lower distalization and relative extrusion of upper incisors.

Photos depict initial panoramic X-ray, teleradiograph and cephalometry.

Fig. 21.49 Initial panoramic X‐ray, teleradiograph and cephalometry.

Requirements for the Technician

  • Provide expansion to the arches by changing torque, applying labial crown torque to premolar and molars of the upper and lower arches during simultaneous distalization
  • Simultaneous distalization of molars, and when the molars achieve their final position distalize 5 to 5 in a row
Schematic illustration of mechanics of simultaneous distalization from temporary anchorage devices in the tuberosity.

Fig. 21.50 Mechanics of simultaneous distalization from temporary anchorage devices in the tuberosity.

Photos depict temporary anchorage devices in left tuberosity failed. It was changed between 26 and 27 to finish the upper left distalization with a sectional wire..

Fig. 21.51 Temporary anchorage devices in left tuberosity failed. It was changed between 26 and 27 to finish the upper left distalization with a sectional wire.

Schematic illustration of mechanics with temporary anchorage device in the tuberosity.

Fig. 21.52 Mechanics with temporary anchorage device in the tuberosity.

Schematic illustration of mechanics for upper and lower simultaneous distalization. Opening space for missing 13.

Fig. 21.53 Mechanics for upper and lower simultaneous distalization. Opening space for missing 13.

Treatment Summary

  • The treatment was completed in 25 months
  • The initial, the patient had 45 aligners which were changed on a 10‐day protocol, and a set of additional aligners to settle the final occlusion
  • The patient used triangular elastics for night use during the treatment to maintain a class I relationship during the distalization
  • The implant for 36 was placed during the treatment and the implant for 13 was placed at the end of the treatment
  • A Powerarm was needed to upright the root of upper first right premolar to place the implant of 13
  • The open bite was closed without increasing the gummy smile of the patient
  • During osteointegration of the implant a composite veneer was placed in 13
Schematic illustration of simultaneous distalization of lower arch using temporary anchorage devices in retromolar zone.

Fig. 21.54 Simultaneous distalization of lower arch using temporary anchorage devices in retromolar zone.

Photos depict initial views before refinement. Opening space for missing 13, uprighting 14 to place implant and implanting of 36 and provisional crown.

Fig. 21.55 Initial views before refinement. Opening space for missing 13, uprighting 14 to place implant and implanting of 36 and provisional crown.

Photo depicts final panoramic X-ray, after placing the implant for 13 and removing temporary attachment devices.

Fig. 21.56 Final panoramic X‐ray, after placing the implant for 13 and removing temporary attachment devices.

Photos depict initial and final intraoral images with composite veneer for 13 inserted while the patient waits for the osteointegration of the implant.

Fig. 21.57 Initial and final intraoral images with composite veneer for 13 inserted while the patient waits for the osteointegration of the implant.

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Related posts:

  1. Predictability of Movement
  2. Treatment Monitoring and Appointments Protocol
  3. Digital Workflow
  4. Basic Principles with Aligners
  5. Arch Length Discrepancies
  6. Sagittal Discrepancies

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Feb 27, 2022 | Posted by in Orthodontics | Comments Off on Vertical Problems

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