1. Weekly Aligner Changes
Data Analysis

2. Weekly Aligner Changes Background
Weekly Aligner changes is in line with market needs
Patients want shorter treatment times
Many doctors are trying already different approaches to shorten treatment time
Innovations of Invisalign system resulting in greater predictability
Invisalign innovations including SmartTrack material and SmartForce features are clinically proven to improve control of tooth movement with Invisalign clear aligners
Hypothesis that treatment predictability of weekly aligner changes is non-inferior to 2-week wear
Data analysis >200 one week wear cases to test the hypothesis

3. Weekly Aligner Changes The data analysis
>200 known in-progress weekly aligner cases with secondary scans available from a small group of doctors
No alternations made to the default tooth movement velocity across those >200 cases
No acceleration devices were used across those cases
A broad range of cases complexity and reduction in Peer Assessment Rate (PAR) scores
Treatment predictability was compared for one week wear cases versus 2 week wear cases using scanned overlays (achieved versus planned treatment).
To measure the tooth movement predictability, we compare achieved vs. planned tooth movement
Data on file at Align Technology

4. Weekly Aligner Changes Quantitative Methodology
Scanned overlays
Initial
(1st scan/impression)
Treatment Predictability is measured by comparing achieved vs. planned treatment for the following metrics:
- PAR score
- Crowding
- Overjet
- Overbite
- Arch expansion
Comparison of outcome parameters includes:
- Number of stages in primary treatment
- Primary treatment duration
- Rate of secondary orders
Planned
(final stage in ClinCheck Software)
Superimposition to compare achieved vs. planned for 1-week wear cases and for 2-week wear cases
Achieved
(2nd scan/impression)
To measure the tooth movement predictability, we compare achieved vs. planned tooth movement
Conclusion: No difference in predictability between 1-week wear cases and 2-week wear cases while reducing the primary treatment duration significantly

5. Weekly Aligner changes Case Complexity of WAC cases: Peer Assessment Rate (PAR) score
Conclusion: For the comparison, case complexity of one week wear cases was equivalent to that from the Asia Pacific sample, the North America sample, and a sample gathered Globally. One week wear cases were of similar complexity when evaluated by initial PAR scores.

6. Weekly Aligner Changes The Recommendation
Weekly aligner changes are recommended for all Invisalign treatments -with default staging protocol—for Invisalign Full, Invisalign Teen, and Invisalign Assist products
The decision to prescribe weekly aligner changes is at the doctor’s discretion
Monitor tooth movements such as rotations, extrusions, and significant root movements; particularly blue and black movements in the Tooth Movement Assessment (TMA)
Depending on the patient response to treatment, particularly mature adults, consider longer periods between aligner changes 
Invisalign, Invisalign Teen, and ClinCheck, among others, are trademarks and/or service marks of Align Technology, Inc. or one of its subsidiaries or affiliated companies and may be registered in the U.S. and/or other countries.

7. Weekly Aligner Changes
Data Analysis for 14 stages

8. 14 stage data analysis Background and Methodology
Treatment predictability was compared for Invisalign Lite (14 stage product) treatments vs. Invisalign Full treatment and Invisalign Teen treatment.
A broad range of cases* of additional aligner scans were analyzed.
Tooth movement effectiveness was measured by overlay analysis of achieved treatment vs planned treatment.
*based on 2 week wear. Refinement rates or treatment times not evaluated

9. 14 stage data analysis Results and Conclusions
Predictability of tooth movement with Invisalign Lite (14 stage product) is comparable to that of Invisalign Full and Invisalign Teen treatment. However, less efficacy was observed in difficult movements including root movements and extrusion.
Since Invisalign Go is also a 14 stage-product, similar to Invisalign Lite, extrapolation of the results was made to include Invisalign Go treatment.
Claim:
In terms of tooth movement predictability, analysis* shows that 14 stage treatments (or Invisalign Lite treatments) are comparable to Invisalign Full and Invisalign Teen products.
Therefore, weekly aligner change can also be recommended for Invisalign Lite and Invisalign Go products.
To measure the tooth movement predictability, we compare achieved vs. planned tooth movement
*Data on file at Align Technology, as of January 2017: Total number of tooth movement analyzed was 112.
Data on file at Align Technology

10. Weekly Aligner Changes Updated Recommendation
Weekly aligner changes are recommended for all Invisalign treatments -with default staging protocol—for Invisalign Full, Invisalign Teen, Invisalign Lite, Invisalign Assist and Invisalign Go products
The decision to prescribe weekly aligner changes is at the doctor’s discretion
Monitor tooth movements such as rotations, extrusions, and significant root movements; particularly blue and black movements in the Tooth Movement Assessment (TMA)
Depending on the patient response to treatment, particularly mature adults, consider longer periods between aligner changes 
Invisalign, Invisalign Teen, and ClinCheck, among others, are trademarks and/or service marks of Align Technology, Inc. or one of its subsidiaries or affiliated companies and may be registered in the U.S. and/or other countries.