Short answer: IPR in orthodontics, or interproximal reduction, is a procedure in which a very small amount of enamel is removed under the doctor's control from the side surfaces where neighboring teeth touch, in order to gain space. It can be used for mild crowding, tooth size discrepancy and situations where extraction is to be avoided. The amount is planned separately for each patient, and there are alternatives. Whether it is needed is decided after the exam and records.
IPR in orthodontics, or interproximal reduction, is the controlled thinning of a very thin layer of enamel from the side surfaces where neighboring teeth touch. The aim is to gain, under the doctor's control, the small amount of space needed to align the teeth. Although the name can sometimes sound frightening, when used for the right indication and in measured amounts it is a planned step that is widely used in orthodontics. In this article you will find what IPR is, why it may be needed and what to watch for.
What is IPR (interproximal reduction)?
IPR is the abbreviation of "interproximal reduction," and in Turkish it is also called arayüz aşındırma or diş arası mine inceltme. A small fraction of a millimeter of enamel is taken from the facing side surfaces of the teeth, and the surface is polished smooth again. In this way, the space in which crowded teeth will settle is increased, or the tooth shapes are made more compatible with one another.
The procedure is not random filing; it is a step in which, in the treatment plan, it is determined in advance how much will be taken from which surface of which tooth. To become familiar with general concepts, you can also look at our dental glossary.
Why might IPR be needed in orthodontics?
IPR comes into play when there is not enough room in the jawbone to align the teeth, or when space is needed because of the shape and width of the teeth. The most common reasons are as follows:
- Mild and moderate crowding: Situations with a small space shortage where teeth overlap.
- Tooth size discrepancy: An imbalance between the widths of the lower and upper teeth can affect the bite.
- Triangular-shaped teeth: In teeth that leave a "black triangle" gap below the gum when the spaces close, to move the contact point to a more suitable place.
- Stability after treatment: When the teeth make good contact with each other, keeping the results can become easier.
- Aim of avoiding extraction: As an option when looking for a solution without extracting teeth in cases of a mild space need.
If the space need is substantial, IPR alone is not enough. In that case, options such as expanding the jaw, moving teeth backward or, in some cases, extraction are evaluated. For general information on crowding, you can look at our page on clear aligners for crowded teeth.
How is IPR done?
IPR is performed by the doctor with special reduction instruments and, in most cases, without the need for anesthesia. The tools used are thin metal strips, enamel reduction burs or small discs. The doctor first places a measuring tool or strip between the teeth to check how much space is being taken. Then the procedure is carried out to the determined amount, the surface is polished, and protective applications recommended by the doctor may be done to support the enamel.
The procedure is often completed in a single session and in a short time; in some patients it can be divided into several sessions over the course of treatment. In other words, the space need can be met step by step as the plan progresses rather than on the first day of treatment. In clear aligner treatment, the timing of IPR is determined according to the stage shown in the digital plan.
Is the enamel thick enough? Is IPR safe?
When planned correctly, IPR is generally considered safe, because the amount of enamel taken from each surface is only a small fraction of a millimeter, and the tooth's enamel layer is thick enough to tolerate it. Enamel thickness varies by tooth and region; in areas where the enamel is thin, such as the lower front teeth, a smaller amount may be appropriate, while in the molars a larger amount may be suitable. For this reason, the same amount is not applied to every patient.
Safety is ensured by the doctor's measurements and the intraoral exam. When necessary, X-ray images help evaluate enamel thickness and the spaces between the teeth. In people who have cavities, gum disease or very thin enamel, the IPR plan may be reconsidered. Trying to file between your teeth on your own is strongly discouraged.
Are there sensitivity and cavity risks after IPR?
After IPR, some people may notice temporary sensitivity to hot, cold or sweet things; this often eases within a short time. When the surface between the teeth is polished smoothly and oral care is adequate, it has not been shown that the risk of cavities increases markedly. Even so, you need to take care to use floss or an interdental brush so that plaque does not build up on the reduced surfaces.
If sensitivity does not go away for a long time or becomes more severe, a check-up appointment should definitely be made. For the general causes of sensitivity and measures that can be taken at home, you can read our article on tooth sensitivity. Fluoride applications or special toothpaste recommendations should be left to the doctor's decision.
What should the patient pay attention to before and after IPR?
Before the procedure, cavities and gum problems are expected to have been treated, because the surfaces to be reduced need to be healthy. Before starting treatment, be sure to tell your doctor about your history of sensitivity, the medications you use and any teeth-clenching habit. This information can be a guide in planning the amount of reduction.
After the procedure, it is helpful to take more care than ever with cleaning between the teeth. You can ask your doctor which tools, such as floss, an interdental brush or a water flosser, are suitable for you. Attending appointments regularly makes it easier to check the areas where IPR was done and the neighboring teeth. If you feel a slight roughness after the procedure, tell the doctor at the check-up appointment rather than intervening on your own.
What is the role of IPR in clear aligners and braces?
IPR is a method that can be used in both clear aligner and bracket treatment; what determines the method is not the type of appliance but the space need. In clear aligner treatment, the digital plan shows in advance how much space will be gained on which tooth surface and at which stage the procedure will be done. Because aligners progress in stages, IPR is sometimes performed during treatment as well. You can find an outline of this process on our clear aligner treatment page.
In bracket treatment, IPR is planned together with the wire movements. At our clinic we use Invisalign as our clear aligner; for general information about wire treatment and other methods, you can read the article what is orthodontic treatment.
What are the alternatives to IPR?
IPR is not the only way to gain space; the doctor evaluates the bite structure and jaw measurements and chooses the most suitable method. The main alternatives are as follows:
- Jaw expansion: Especially in growing patients, if the upper jaw is narrow, the space need can be met by expansion.
- Moving teeth backward (distalization): Space is gained by guiding the molars backward; it cannot be applied in every patient.
- Tipping teeth forward: Tilting the front teeth slightly forward is an option as far as the profile allows.
- Tooth extraction: Considered when the space need is high and the profile is suitable.
Which path is chosen is determined according to exam findings, tomography or X-ray records and the patient's preference. Non-extraction options are generally handled individually.
When should you apply for an IPR evaluation in Ankara?
You can only find out whether IPR is needed through an orthodontic exam and records; for this reason, it is recommended to have an evaluation before starting treatment for crowding or spacing problems in your teeth. This evaluation is carried out at our clinic in Park Oran Ofis, Çankaya, Oran, and the cost is communicated in writing after the exam and planning. For an appointment, you can reach our contact page.
Frequently asked questions
Does IPR cause permanent damage to the teeth?
Because enamel is a tissue that cannot regenerate, IPR must be done deliberately and in measured amounts. When applied in the small amounts planned under the doctor's control, the health of the tooth is generally preserved; the amount is determined separately for each patient.
Is pain felt during the IPR procedure?
In most cases anesthesia is not needed, and the procedure is done with a feeling of mild pressure. In patients with sensitivity, the doctor plans the procedure with this in mind.
Do the spaces between teeth that had IPR open up again?
The reduced surfaces are closed during treatment so that they contact the neighboring teeth. To maintain the results, retainer use should be continued as the doctor recommends.
Is IPR necessary in every orthodontic treatment?
No. In cases with no space need, or where it can be met by other methods, IPR may not be used at all. The need is determined according to the exam and the treatment plan.
How long does sensitivity last after IPR?
In most people sensitivity passes within a short time. If it lasts long or gets worse, you should see your doctor; leave the choice of medication or product to the doctor.