Pulpotomy (Summarized by Jenny Sheets)

If a tooth gets a large cavity, the bacteria in the decay can damage the Pulp, which is often what causes toothache. When the soft tissue in the Pulp Chamber is infected (has bacteria in it) or affected (is inflamed) but the soft tissue in the canals is still healthy, a special procedure called pulpotomy can be done by a dentist under local anaesthesia. In this procedure, the dentist will remove the entire pulp in the chamber but leave the vital pulp in the canals. There are two advantages of pulpotomy for children.  First the primary or deciduous teeth only have to survive until adult teeth erupt. Second, this procedure requires much less time than pulpectomy.

 The procedural steps for a pulpotomy are below:

1.  Numb the tooth and tissue.

2.  Isolate the tooth with a rubber dam.

3.  Remove the caries and clean the pulp out of the Chamber.

4.  Clean the chamber and dry it with clean cotton pellets. Apply Formocresol using a cotton pellet in minimal amounts. If too much is applied, use another cotton pellet to absorb the extra fluid. Make sure the exposed root pulp is in contact with Formocresol for four minutes.

    Formocresol is used to disinfect the tooth chamber and stop or slow down the tooth decay.  Be cautious not to apply this chemical to the tissue around the tooth.

5.  Remove Formocresol pellet after 4 minutes. The bleeding should be stopped, and the color of exposed root pulp should look brown.

6.  Mix IRM powder with liquid until it has consistency of medium-firm dough that can be shaped by hand.

IRM was developed as a temporary filling material.  IRM stands for Intermediate Restorative Material. A variation of this material is called Zinc Oxide and Eugenol or "ZOE". This mixture consists of powdered Zinc Oxide and a liquid Eugenol (which is basically oil of cloves). IRM is the same as ZOE but has a reinforcing material added to make it more resistant to wear.

“IRM filling” is known as a Sedative Filling. It will help the patient feel better during and following the procedure. It should also slow or stop the progression of decay, and provide the tooth time to recover and lay down secondary dentin.

7.  Shape the IRM dough to make it easy for the doctor to seal the top of the pulp canals.

8.  After sealing the canals with IRM, mix Ketac powder and liquid to the same consistency as the IRM mixture. Hand shape the Ketac dough and fit it into the chamber to cover the IRM. 

  Pass the doctor dry powder for both IRM and Ketac, which he may use to coat his instruments to facilitate setting the mixtures into place.

At step 8, we seal the pulpotomy with IRM, then place KETAC dough over it for two reasons. First, IRM is very soft and slow setting material. If pressure is applied, the IRM will shift out of position. Secondly, the Eugenol in IRM inhibits Polymerization of the Composite. So KETAC dough is used as a protective cover.

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Xin Wei, DDS, PhD, MS 1st edition 01/29/2013, last revision 01/29/2014