Aligner Dental Academy explains how to plan and deliver interproximal reduction (IPR) in an aesthetic and minimally invasive way.
IPR are the three letters that make many dentists shudder when they see it on their clear aligner plans!
Given GDPs are masters of enamel reduction when it comes to any restorative work, why is it there is such reservation when it comes to carrying out minimal interproximal reduction for orthodontic cases?
At Aligner Dental Academy, we have all the tools you need to tackle IPR head on and ensure you plan and deliver it in the most aesthetic and minimal way.
Techniques for completing IPR
1. IPR strips
This is the most user-friendly way of completing IPR! Strips will allow you to perform IPR in a very controlled and precise manner. There are three strips differing in size:
1. Yellow: 0.08mm thickness
2. Red: 0.1mm thickness
3. Blue: 0.14mm thickness.
If you are new to completing IPR or the IPR needed is less than 0.3mm you can safely use strips to complete the prescribed amount.
See our demo video of IPR being performed using strips here.
2. IPR burs
Burs are helpful when heavier IPR (0.4-0.5mm) is planned and can be more efficient than using strips. There is a higher risk of iatrogenic damage when using burs, it is easy to take away too much or create ledges. A slow and controlled brushing movement is a good way to use burs when performing IPR and make sure you polish the contacts after with a yellow strip.
See our demo video of IPR being performed using strips and burs here.
3. IPR discs
IPR Discs are an alternative way to complete IPR once you have opened the contact with a strip. If using a disc be careful to use an Optragate or similar to reduce the risk of soft tissue lacerations. When completing IPR using discs make sure you hold the disc upright and never at an angle to maintain tooth shape and proportions.
A demo using IPR discs and more advanced IPR techniques can be accessed here.
ADA’s top tips for performing interproximal reduction
1. Remember the safe limits
Ideally limit IPR around the anterior teeth to 0.3mm and increase IPR up to 0.5mm around premolars and molars.
Lower incisors have the thinnest approximal enamel 0.7-0.8mm per surface (1.4-1.6mm of total enamel in the embrasures).
Upper incisors have 0.9mm of approximal enamel thickness (1.8mm total enamel thickness in the embrasures).
Canine approximal enamel is 1-1.2mm and it jumps up by another 0.1mm for each tooth moving distal to the canine.
2. Stage IPR
If the contacts are very displaced you may want to wait for access to be easier before performing IPR. This will help maintain the anatomy of the interproximal area. You can change the stage that IPR is planned by asking the technician via the ClinCheck modification tab.
3. Check for ledges
After completing IPR, ensure you smooth the contact with a yellow strip. Use floss to check you have not accidentally created a ledge.
4. Use a gauge
Make sure you measure and record how much interproximal reduction has been completed at each appointment. A gauge is essential for doing this.
5. Still unsure? Ask for help!
There are numerous resources available on ADA to increase your confidence when completing IPR.
See Dr Raman Aulakhs TED Talk on ‘Is IPR dangerous?’ here.
Hands-on IPR education
We also run a hands-on course at Londec that covers all aspects of IPR with our experienced mentors on hand to ensure you are completing it correctly.
Our Londec course is an excellent resource for any practitioner wanting to upskill in Invisalign. As well as IPR techniques the following is covered on the day:
- Direct placement of bonded retainers
- ClinCheck clinic (including 3D controls)
- Perfecting your Invisalign cases: attachment removal, enameloplasty, and retention essentials
- Class II and III elastics
- Troubleshooting with elastics
- Q&A session to address all your queries.
Each date last year was sold out and the feedback has been extremely positive!
ADA’s Londec course is available to both ADA members and non members. For more information see alignerdentalacademy.com/new-events/live-invisalign-skills-lab/.
This article is sponsored by Aligner Dental Academy.
