Ask a doctor

How Are Invisalign Trays Numbered?

I am finished with my treatment & have saved my last 2 sets of aligners incase my retainers broke. Well, my retainer broke and I'd like to use my last set again until my new retainer comes in. I have one set that's labeled 03 and one that is 04. I can not remember which was the last set in my case.

Doctor Answers (3)

The Higher the Number the Closer to Finishing


When it comes to Invisalign trays, typically the higher number would be the last set. So if you have a higher number than odds are that is where you left off.

New York Orthodontist

Numbers are laser inscribed on each aligner


There is an U for the upper and an L for the lower and there is a number next to that which signifies the aligner. Use number 4. If you only had 4 aligners then thats your last one and its safe to wear. If you had 10 or 20 then number 4 is not recommended to wear.

Michael J. Thomas, DDS
Los Angeles Cosmetic Dentist
1.0 out of 5 stars 1 review

Normally invisalign is numbered low to high


The first aligner is #1 and the last one is #20 (if there were 20).  It sounds like you were an Express case?  only 4 total? 

In a pinch, the dental office can take impressions and send to a local lab.  Normal turnaround time for this is only 2-3 days.

Lance Timmerman, DMD
Seattle Cosmetic Dentist
5.0 out of 5 stars 3 reviews

You might also like...

These answers are for educational purposes and should not be relied upon as a substitute for medical advice you may receive from your physician. If you have a medical emergency, please call 911. These answers do not constitute or initiate a patient/doctor relationship.