Interproximal reduction (IPR) is another way of saying “adjusting your tooth width.” IPR is the conservative removal of some of the outer tooth surface, called enamel. 
What Is The Purpose Of IPR?
Usually, only about .1-.25mm of enamel, a minuscule amount, is removed on each surface. This technique has been used in orthodontics since the 1940s. IPR is also known as slenderizing, re-contouring, and reproximation. Sometimes patients refer to it as “filing,” “shaving” or “stripping,” but those terms just don’t do justice to the great care and finesse with which most IPR is done by orthodontists!
After the enamel is reduced, the remaining enamel is tediously smoothed and curved to re-establish the natural contours.
Whatever the name, the intentions are the same:
- To acquire more space for your teeth
- To reduce friction between your teeth, facilitating movement
- To improve your bite, or
- To make the teeth shapes more attractive and reduce the triangle of dark space between triangular teeth when the gums don’t reach the point of contact between teeth.
If you have teeth that are not straight or overlapped, it’s almost always because those teeth are too big relative to the fixed ridge of bone the teeth live on. If you align crowded teeth simply by proclining them forward, in some cases you can risk gum recession or bite instability. Making each tooth a little bit smaller helps them fit better on the bone ridge. It also makes them less likely to shift after treatment, in this way contributing to stability. 
The Procedure
When IPR is performed, tooth enamel is either smoothed manually with a very thin, very fine, flexible abrasive strip, or with the aid of a specially-designed dental handpiece. During the procedure, the orthodontist may push a latex wedge in between your teeth to create a slight separation for easier access to the interproximal surface. This wedge also protects the gums. Your gums may get scratched during this procedure, but you may not even feel it.
Tooth enamel is a bit like your fingernails—it has no innervation. The tenths of millimeters removed with IPR do not hurt, do not require anesthesia, and can be done in a matter of a few minutes. Studies have shown that when done properly, it does not increase your risk for cavities or sensitivity.
IPR is more common with adult orthodontic treatment and with aligner treatment than with child and adolescent treatment and braces. With kids, we are more likely to take teeth out when there is significant crowding rather than reduce teeth widths. This is in part because it is easier to close large spaces in growing kids and with braces.
If Dr. Pompei recommends interproximal reduction, she truly believes it is the right thing to do and has seen excellent long-term results in other patients! Don’t hesitate to ask any questions you may have regarding this procedure.
