2813 North Hurstbourne Parkway, Louisville, KY 40223
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Let's Talk about IPR


If you don’t love your smile because of “dark triangle” spaces, you may consider enhancement orthodontics with interproximal reduction (IPR). IPR is a technique where an artistic and trained orthodontic specialist polishes between the teeth using a small disc or strip, going through the contact point, creating a temporary small space. The orthodontist then closes the space by using braces or clear aligners. The small space usually closes within a matter of days and the end result is a reduced or completely eliminated dark triangle.

Dark triangles are quite common. The following are factors contributing to dark triangles (aka “open gingival embrasures”):

1. Crowded teeth – The gums are contoured around overlapping teeth, so when the teeth are straightened, the gum recession is “unmasked,” revealing the dark triangle.

2. Triangular shaped teeth – In contrast to rectangular shaped teeth, triangularly shaped teeth have a very small point contact near the biting edge of the tooth. This leaves a large triangular space between the teeth that the gums often cannot fill.

3. Bone position around the teeth – If the point where the teeth contact is more than 5 mm away from the level of the bone supporting the teeth, there will be a dark triangle


1. IPR is not harmful to the enamel. Multiple university studies have proven that the enamel after polishing is actually smoother than natural enamel, and is NOT weaker or at higher risk for cavities/decay.

2. IPR is not painful unless the gum tissue is severely swollen. The teeth/gums do not need to be numbed prior to completing IPR.

3. Closing the dark triangle results in a more beautiful smile!

4. IPR can promote healthier gums and teeth, because closing the space reduces/eliminates the dark triangular space that can be a trap for food, bacteria, plaque, and tartar.

5. It promotes better orthodontic stability, which means less chance of shifting and relapse after orthodontic treatment, because the previous very small “point contact” between the teeth is more prone to shifting than a broad contact with greater surface area between the teeth.


Illustration of IPR


Before and After IPR

Credit: Dr. Brian Anderson
