Also See:
Basic Principles of Clear Aligner Treatment , Checklist for Clear Aligner Success

IPR (Interproximal Reduction)

While OrthoSnap clear aligners are designed to eliminate or greatly reduce the need for IPR (interproximal reduction), some patients may require one or more to achieve the best results.  

With IPR, a small space is created by reducing the proximal surface of a tooth. This is sometimes needed to help the teeth move to the desired position.  

Before performing IPR, keep the following important information in mind to help increase patient comfort and reduce anxiety. 

First Things First

  • OrthoSnap will make recommendations for the location and amount of IPR needed, but these are only recommendations.

  • As the treating doctor, the final decision and any necessary changes are up to you. 

  • You can always reach out to our support at for additional recommendations or if you have any questions.

Inform the Patient

Explain the procedure to the patient or guardian, making sure they fully understand the procedure and that the result will be a misshapen tooth. (This doesn’t increase the risk of dental decay.) 

Discuss improbable but possible risks, including:

  • Discomfort or sensitivity

  • Pressure sensation

  • Feeling vibrations on the tooth

  • Possible bleeding lips, gums, or cheeks

Once you have answered all the patient’s questions, and they fully understand and agree, be sure to get an informed consent signed. 

Pre-IPR Preparation

  • Evaluate whether or not it is best to perform the IPR at this appointment. If the patient needs more than one, you do not have to perform all of them at the same time. 

  • If the patient has excessive rotation or crowding, pre-IPR separation may be needed. 

This involves the use of an orthodontic separator, also known as a spacer, placed between overlapping teeth. The spacer—either a rubber band or wire—will move the teeth apart to allow interproximal access. Depending on the severity of crowding, the spacer may need to stay in place for a couple of days. With minor crowding, it may do its job in a matter of minutes. 

  • Decide which teeth and which surfaces need reduction.

  • Choose your preferred method and instruments. For instance, depending on the amount of IPR needed, you may choose double-sided discs, single-sided discs, or abrasive strips. 

Here is a guideline you can follow:

To achieve a 1 mm IPR, you can use either 0.13 mm (medium), 0.10 mm (fine), or 0.08 mm (extra fine) abrasive strips.

To achieve a 2 mm IPR, you can use a 0.1 mm one-sided disc. 

For a 3 mm IPR, you can choose either a 0.2 mm or 0.15 mm two-sided disc. Gently move the disc back and forth distally and mesially in the interproximal space to achieve the desired reduction. 

Performing IPR

  • For patient comfort, consider the use of a topical anesthetic.

  • Check compliance with unwaxed dental floss. Look for contact between teeth.

  • Consider the use of a disc guard if access is questionable.

  • If more than one IPR is needed, start posteriorly and progress anteriorly.

  • Remember to allow the instrument to do the cutting—only use light pressure. 

  • Keep the RPM low until you achieve the desired angulation. Then, increase RPM to perform the reduction.

  • While performing the reduction, have an assistant direct a stream of air across the site, away from you and your patient’s face.

  • Diligently observe the lingual and labial aspects, making sure you cut the teeth appropriately. 

Final Steps

  • Stop the instrument and carefully push it against the gum to ensure the contact is fully broken. 

  • Using an IPR thickness gauge, confirm the interproximal space. 

  • Angulate the cuts to improve the appearance of the tooth.

  • Using floss or an explorer, check for ledges or nicks on the tooth. 

  • Round off sharp corners with abrasive strips or diamond bur. 

  • Document the IPR, including the location and amount. 

Related Topics and Information:

Click to learn more about Basic Principles of Clear Aligner Treatment and see a  Checklist for Clear Aligner Success.

If you have questions or need to speak with someone at Orthosnap, please reach out to us at

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