de_DEen_GBen_USes_ESfr_FR is reader-supported. When you buy via the links on our site, we may earn an affiliate commission at no cost to you. Learn more.

What is Interproximal Reduction (IPR) and Why Do You Need It?

Amanda Dexter
Amanda Dexter
Medically reviewed by
Dr. Clarke Stevens
calendar icon
updated icon

Do you need interproximal reduction (IPR) before getting dental braces? If you have been told this, you may wonder: what is an interproximal reduction and is it really necessary?

Dentists and orthodontists use fixed braces and removable invisible braces such as Invisalign to treat crooked teeth. To provide some extra space between teeth so that they can adjust correctly, your orthodontist might recommend a procedure called interproximal reduction, otherwise known as IPR.

IPR is a dental treatment that involves removing tooth enamel in between adjacent teeth. The purpose of the procedure is to create more space for better alignment and to correct issues like crowded teeth. This procedure can improve your bite and make your smile more attractive. 

IPR is also referred to as slenderising, selective reduction, or interproximal stripping, and is recommended in certain situations by orthodontists worldwide.

Do I really need IPR?

This primarily depends on what your dentist or orthodontist finds during your orthodontic exam. The size, shape, alignment, and position of your teeth will determine whether they need reshaping. The goal is to improve the health of your teeth, so your dentist or orthodontist will decide based on what will work best for you.

interproximal reduction
IPR involves removing tooth enamel from
between adjacent teeth to make space for alignment

The front teeth framework and their position can change your facial appearance completely. Your orthodontist will determine your interproximal reduction needs by assessing your teeth and bite through photographs, x-rays, and digital scanning equipment such as Invisalign's iTero scanner.

Usually, IPR is relatively painless because the outer layer of the tooth doesn’t have any nerve endings, though you may feel some discomfort or sensitivity during the procedure. After your teeth are smoothed and polished, you should see a visible difference in your facial characteristics.

To get a better understanding of the concept and procedure involved, watch this video from Dr Greg Asatrian.

Do you need IPR before Invisalign aligners?

The Invisalign system is a series of removable clear plastic aligners that use pressure to gradually straighten and align your teeth. They work like invisible braces that you can conveniently remove to eat, drink, and clean your teeth. Many people who get treatment with these aligners have crowded teeth, which Invisalign IPR can help with.

IPR can help to create space between teeth so that the aligners can align and straighten them more easily. It is not uncommon to have this procedure before starting your treatment if your Invisalign doctor thinks that is necessary.

If you are considering Invisalign aligners but you're not sure if you would need IPR first, it's best to speak to an Invisalign doctor. Simply use Invisalign's postcode search to find your nearest provider and book an appointment!

Enamel reduction techniques in IPR orthodontics

There are both mechanical and manual methods of interproximal reduction, and your orthodontist will use the most appropriate method for your case.

The manual method of teeth reduction mainly involves the use of metallic IPR strips coated with metal oxides, abrasive discs, or air rotor stripping. These metal IPR strips can be handheld or motor-driven and are used for anterior and minor tooth reduction.

Your orthodontist will use them for re-contouring the anterior and minor teeth. This technique is less aggressive than the mechanical system, and patients report some discomfort. With any method of IPR dental treatment, you may experience some sensitivity after the procedure.

There are different manual methods, but let's look at the most common clinical ones.

Air rotor stripping with fine tungsten-carbide or diamond burs

This method ensures precision in the reduction of interproximal enamel. It allows the orthodontist to create space between teeth quickly, and there’s no need to extract teeth with this procedure.

Abrasive diamond discs

Orthodontists use these discs if they have to remove more enamel than abrasive strips can handle, both for separating and contouring. Available in different sizes, they can be double or single-sided.

There are mechanical methods as well that use heat and vibration to smoothly cut the teeth. Mechanical reduction tools include discs and mechanical files for added precision in removing tooth tissue with little pressure.

Here’s a comparative chart of manual and mechanical enamel reduction techniques:




  • No risk of cutting into the soft tissue

  • Enamel surface is smoother

  • Disc guard is used to protect the patient

  • Reduces working time


  • Chance of debris being left behind

  • Time-consuming when used for buccal teeth

  • Risk of excessive enamel reduction

  • Not flexible

What is the interproximal reduction process?

IPR isn’t a cumbersome process. It typically involves a few steps, including:

  1. Planning
  2. Preparation
  3. Reshaping
  4. Polishing
  5. Fluoride treatments

Let's dive into each stage and discuss exactly how it all works.

Step 1: Planning

In this step, the orthodontist determines the extent of enamel reduction needed. For this, the exact morphology of your teeth needs to be examined. Calibrated radiographic images are the most feasible clinical application used to identify exactly which teeth need to be slenderised.

Step 2: Interproximal area access

This is a very important step to protect the proximal areas. At this stage, your IPR ortho will place appliances or guards to protect the proximal teeth prior to interproximal stripping.

Ask a dentist: Is Interproximal Reduction (IPR) painful?

It may sound scary when your orthodontist tells you he or she needs to file down some of your teeth to create more space between them, but the procedure can sometimes be a necessary step in straightening your teeth.

An orthodontist will polish the surfaces in between your teeth so that they can move more easily into a better position. It only affects the outer layer of the tooth, and because the enamel doesn’t have any nerve endings, the patient will not really feel any pain.

There may be some discomfort during the procedure, but nothing to be too concerned about. IPR often involves simply using extremely fine strips of dental sandpaper or other dental tools specifically designed for the procedure.

Dr Clarke Stevens

Step 3: Protecting soft tissues

The ARS (air-rotor stripping) guidelines clearly suggest using brass or steel indicator wire to protect the soft tissue. This type of hardware will protect your oral tissues from interproximal gingival lesions that the revolving diamond disc can cause.

Step 4: Interproximal enamel removal by manual or mechanical methods

IPR teeth
IPR can be carried out using manual or
mechanical methods.

People often criticise manual methods for performing this procedure because they’re time-consuming and some research suggests that it doesn't work for posterior teeth.

Considering the advantages over manual methods, mechanical methods (such as the use of diamond discs or segment discs) are becoming the first choice for orthodontists.

This is because discs can rotate 360 degrees, giving the orthodontist better visual access, which is very important in minimising the risk of errors. Disc guards are also mounted over the handpiece to protect the adjacent teeth.

Step 5: Finishing and polishing the enamel surface

The last and final step of the procedure includes polishing the corners of the IPR teeth with a cone-shaped triangular diamond burr. This process is also called re-contouring. After tooth reduction, it’s very important to carefully shape the teeth to the original contours.

Step 6: Topical fluoride treatments

After you complete the above-mentioned steps, your orthodontist may treat tooth surfaces with fluoride gel to prevent enamel demineralisation.


Interproximal reduction might sound like a complicated procedure, but for orthodontists, it’s a routine process that’s meant to enhance the results of teeth straightening treatments, like braces.

With the increasing demand for aesthetics and customised approaches to treatment, this method has evolved and emerged as an alternative to archwires and brackets.

You can have IPR done before treatment with the Invisalign system to help crowded teeth move into a better position and improve the overall appearance of your smile.

If you're thinking about getting these aligners, take a Smile Assessment to find out if you're eligible. Or, book an appointment with your nearest provider to find out more about straightening your teeth with Invisalign aligners and if you need IPR first.

Before/after results with our #1 recommended teeth aligners

Use “DENTALY5OFF” to get an additional 5% discount.


What does IPR mean in orthodontics?

IPR stands for interproximal reduction, a technique used by orthodontists to create temporary space between the teeth to create more space for teeth to move during orthodontic treatment.

Will interproximal reduction damage my teeth or gums?

Studies have shown that a patient who has gone through interproximal reduction is less susceptible to tooth decay and gum diseases. However, tooth reduction may cause some sensitivity. This is common with many types of dental treatments.

What is Interproximal Reduction (IPR) and Why Do You Need It?
5 (100%) 1 vote[s]


NCBI: Enamel reduction techniques in orthodontics. Consulted 4th April 2022.

JDAO-Journal: Clear thinking about interproximal stripping. Consulted 4th April 2022.

Bentham Open: Enamel reduction techniques in orthodontics: A literature review. Consulted 4th April 2022.