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

Do you need interproximal reduction (IPR) before getting adult braces? What is interproximal reduction, anyway?

Braces are orthodontics used to treat crooked teeth. In order to provide some extra space between teeth so that they can adjust correctly, your ortho might recommend a procedure called interproximal reduction, or IPR. IPR involves removing tooth enamel in between adjacent teeth.

The purpose of the procedure is to create more space between teeth for better alignment and to correct issues like crowded teeth. This procedure is usually done to improve your bite and make your smile more attractive. 

IPR is also referred to as slenderizing, selective reduction, or stripping and has been recommended by orthodontists worldwide.

Do I really need IPR?

The answer to that question is primarily dependent on the orthodontic exam. Factors such as size, shape, alignment, and position of your teeth will determine whether or not they need reshaping. The ultimate goal here is to improve the health of your teeth.

The front teeth framework and their position can change your facial appearance completely. Evaluation is done through photographs or x-rays, and after that, the IPR ortho determines your reduction needs.

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. Also, after your teeth are smoothed and polished, you’ll 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.

Enamel reduction techniques in IPR orthodontics

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

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

Your IPR 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, 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 burns

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

These discs are used if orthodontists need 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. Mechanical reduction tools include discs and mechanical files. These are used for added precision in removing tooth tissue with little pressure. Only heat and vibration is used to cut the tooth very smoothly.

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

What is the interproximal reduction process?

IPR isn’t a particularly cumbersome process. It typically involves a few steps, including the planning stage, prep, reshaping, and ending with polishing and fluoride treatments. Let's dive into how it all works.

Step 1: Planning

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

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 stripping.

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 can be caused by the revolving diamond disc.

Step 4: Interproximal enamel removal by manual or mechanical methods

Manual methods for performing this procedure are often criticized because they’re time-consuming. Also, 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.

Because they can rotate 360 degrees, discs give the orthodontist better visual access, which is very important in minimizing the risk of errors. Disc guards are also mounted over the hand piece 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 the above-mentioned steps have been completed, your orthodontist may treat tooth surfaces with fluoride gel to prevent enamel demineralization.

Conclusion

Interproximal reduction might sound like a complicated procedure, but for orthodontists, it’s a routine process that’s meant to enhance the results of other teeth straightening treatments, like braces. With the increasing demand for aesthetics and customized approaches to treatment, this method has evolved and emerged as an alternative to arch wires and brackets.

FAQs

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.