April’s Tip

Aligners-Thoughts and Tips Part II

By Dr. Adrian J. Palencar, MUDr, MAGD, IBO, FADI, FPFA, FICD

April 2024

IAO Diplomate
68 – Tremont Drive, ST. Catharines
ON L2T 3B2, Canada

Interproximal Reduction (IPR) up to 0.5 mm

As the author alluded in the previous Monthly Tip, it is paramount to align rotated and crowded teeth prior to the IPR. Otherwise, the clinician may be slenderizing wrong surfaces. Therefore, in most cases, slenderize later, rather than at the commencement of the treatment.

The author had few cases, where the IPR was done exactly to the request of the Aligner’s producer; however, after the last aligner, there were still open contacts.  Since then, we do IPR a 0.10 mm less then prescribed.  If this is not sufficient, this can be corrected at the Refinement stage.

IPR is an irreversible procedure; therefore, the patient must be informed.  Risks, benefits, alternatives, or the option of no treatment at all should be reviewed.  If everyone agrees, Informed consent must be signed.  The form is attached.


IPR Protocol

  1. Sign the Informed consent.
  2. Pumice the teeth and rinse with Peridex.
  3. Place topical anesthetics (infiltration if necessary)
  4. Separate the teeth (one site at the time) with a rigid wedge.
  5. Perform IPR with an IPR file (preferably in the handpiece)
  6. Measure with an IPR gauge and record the acquired space.
  7. Polish the interproximal surfaces with polishing strips.
  8. Apply Topical fluoride and prescribe fluoride rinse at home.
  9. Rx: Acetaminophen 500 mg p.r.n., (not Ibuprofen, it inhibits the tooth movement)
  10. Give post-IPR instructions.

Opening the contact with the rigid wedge made all the difference.  We did not have to use contact breaking files anymore and the wedge protects the gingival papilla.

The final note, the author prefers to place the handpiece from the lingual aspect, as he feels that he has a better visual control.


  1. Densply Sirona Catalogue
  2. Author’s experience, observation, and research
  3. Palencar A. J., Air-Rotor Slenderizing (ARS), VOL 15 – NO 3, FALL 2004