Invisalign Clinical Best Practices

Protocol

Ask the Expert Call

Dr. René SterentalMarch 30th, 2007

What is the Clinical Best Practices Protocol?

The objective of the BP Protocol is to offer customers the best of what Align knows of how to treat cases with Invisalign.

The protocol is the result of combining the consensus opinions of leading edge user-doctors, research studies, and over 500K cases in treatment.

Implementation of the elements of this protocol through software automation renders them available to all user-doctors in a manner that is repeatable and scalable.

Elements of Invisalign Clinical Best Practices

Protocol

New Staging Protocol

New Attachment Protocol

New Staging Protocol

Sequential Staging (Old Protocol)

Simultaneous Staging (New Protocol)

Sequential Staging (Old protocol)

Individual Teeth: Complex movements required by one tooth (i.e.

rotation + extrusion) are performed separately, with the less predictable movement staged at the end of the treatment.

Staging of multiple teeth per arch : Some teeth start moving earlier in the setup and other

teeth start moving later. Intended to enhance intra-arch anchorage and/or to

avoid collisions between the teeth as they move.

Sequential Staging considerations (Old protocol)

Difficult movements are often left to the end of treatment and may be accelerated beyond the ideal clinical rate of movement required – applies to root movements.

Difficult for the clinician to estimate and request optimal velocity – can lead to request an excessive number of aligners by indiscriminate requests to reduce the velocity by increasing the overall number of stages.

Simultaneous Staging (New protocol)

Different movements on individual teeth:

Complex movements required by one tooth (i.e. rotation + root uprighting) are performed at the same time.

This usually ensures that the less predictable root movement is performed at a reduced velocity since it is taking place along the greater number of stages required by the easier crown movement.

Simultaneous Staging (New protocol)

Staging of multiple teeth per arch:

All the teeth within each arch are moved together from the initial stage through the final stage.

The tooth that moves the most dictates the overall number of stages based on the maximum allowable tooth velocity.

Moving the other teeth simultaneously from the first to last stage reduces the velocity for all the other movements and increases their predictability without increasing the overall number of aligners.

Tooth moving the most determines treatment length.

Upper Arch example

Initial Final

Sequential Staging - Velocity (Old protocol)

Simultaneous Staging - Velocity (New protocol)

25% reduction in the number of stages!

Lower arch example

Initial Final

Sequential Staging - Velocity (Old protocol)

Simultaneous Staging - Velocity (New protocol)

50% reduction in the number of stages!

Automatically handling of collisions, binding and IPR

Movement is not allowed if software does not detect space.

IPR is programmed only on interproximal contacts.

Expansion and proclination are considered before IPR

Original position

If IPR is done at this time, it will remove part of the lingual face in UL1(black

mark)

Final position – Lingual area that would be have to be removed by IPR needlessly since it keeps shifting as the teeth are rotating.

Old IPR Staging

Original positionProclination to place the interproximal contacts in

a better relationship before IPR is allowed

Same final position after doing the IPR and retracting the teeth

New IPR Staging

New Attachment Protocol

Attachments can be…

Passive – Tooth doesn’t move: Intrusion Anchorage Aligner Retentiveness

Active – Tooth moves: Rotations of round teeth Root Control Extrusion

Types of Attachments

Align Technology has three type of attachments for commercial use:

BeveledEllipsoid Rectangular

Horizontal Ellipsoid Attachment

Default for extrusions of anterior teeth

1 mm thick Doctor can request on

any tooth

Incisor Extrusions

1 mm thick horizontal ellipsoid attachments on any anterior tooth that needs to be extruded

Vertical Rectangular Attachment

Default for rotations of cuspids and bicuspids

Default for root control on extraction cases

1 mm thick 3 mm (default), 4 mm or 5

mm long 2 mm wide Doctor can request on any

tooth – very retentive Doctor can request

beveled option

Cuspid & Bicuspid Rotation

1 mm thick vertical rectangular attachments on cuspids and bicuspids that are rotating

Optional on other teeth

1 mm thick vertical rectangular attachments on the two teeth adjacent to the extraction site

Lower Incisor Extraction

1 mm thick vertical rectangular attachments on the two teeth distal and one tooth mesial to the extraction site

Bicuspid Extraction

Rectangular Attachments

Problems with rectangular attachment They don’t always engage as intended

Unintended forces

Optional vertical beveled attachment for rotation (Doctor request)

Beveled Attachment concept

Horizontal Beveled Attachment

Default on first bicuspids as anchorage for anterior intrusion

Beveled incisally (default)

Doctor can request on any tooth for aligner retentiveness or extrusion

Easier to insert and remove aligner

Anterior Intrusion Anchorage provided by horizontal beveled

attachment on first bicuspids

Horizontal beveled attachments bilaterally on the first bicuspids to provide anchorage for anterior intrusion

Anterior Intrusion Anchorage

Vertical rectangular attachments will be used instead on both bicuspids to provide anchorage for anterior intrusion if they are rotated

Anterior Intrusion Anchorage provided by vertical rectangular

attachment on rotated bicuspids

If bicuspids are rotated…

Beveled incisally(Default)

Beveled gingivally(Doctor request)

1 mm

0.25 mm

0.25 mm

1 mm

Horizontal Beveled - Orientation

Vertical Rectangular 1mm prominence Placement on two teeth distal and one mesial to the

extraction site

Vertical Rectangular 1mm prominence Placement on two teeth adjacent to the extraction site

Horizontal ellipsoid 1mm of prominence Default position for extrusion attachments is between

the cervical and middle third of the tooth

Horizontal beveled incisally 1 mm prominence Attachments will be placed bilaterally on the first

bicuspids

Vertical Rectangular is placed instead if bicuspid is also rotating

Vertical Rectangular 1mm prominence

Description for default size and placement

Bicuspid extractions

Rotations of cuspids & bicuspids

Anterior intrusions

Lower incisor extractions

Anterior extrusions

Situation:

Default Attachment Placement Summary

Always review ClinCheck using the Superimposition Tool to determine if attachments are placed on teeth that might need them

By Doctor Request ONLY!

Doctor may request 1 mm thick V ertical Rectangular attachment for mesio-distal root tip.

Root Tip

Doctors may request attachments when retention/anchorage is a concern during certain movements or conditions i.e. expansion or short clinical crowns

M ore than two vertical rectangular attachments per quadrant may provide too much aligner retention.

Aligner Retentiveness

Doctors may request attachments be added starting at stage 2 so the patient can f irst get comfortable in placing and removing aligners with first set without the added retention the attachments provide.

Patient Comfort

A lign does not place attachments on all extrusions by default. Doctor may request attachments for extrusions not included in default.

Extrusions of other teeth

Doctor may request attachments for rotations not included in default. Incisors generally do not need attachments for rotation.

Rotation of other teeth

DescriptionS ituation

Doctor may request Horizontal B eveled attachments placed on the incisal third of upper anterior teeth for bucco-lingual root torque to prevent aligner dislodgment. Root Torque

Always review ClinCheck using the Superimposition Tool to determine if attachments are placed on teeth that might need them

Making Invisalign work better…

Clean up your Treatment Preferences in order to get

consistent quality setups!

Clean up your Tx preferences!

Old Treatment preferences often conflict with the automated Best Practices Clinical Protocols.

View the initial ClinCheck set up with automated protocols for consistent quality.

If needed, modify the initial ClinCheck to address specific problems or preferences. Technicians will tend to use automated protocols

instead of complicated Tx preferences for initial setups.

Thank you!