Tooth preparation for a cast gold post and core

After the completion of re-treatment of root canal therayp (RCT) on #22, a patient presented to the appointment with the tooth being prepared for the post placement.

Before starting the procedure, I took a maxillary quadrant alginate impression of the patient’s mouth. In the maxilla one of the fillings had an overhang so we blocked out the undercut with blue wax placed in the interproximal space from both the buccal and the lingual. Also, we placed some Vaseline on the buccal and the lingual surfaces of that same tooth in order to avoid problem during ejection of the set alginate impression from the mouth.

After the alginate impression, we went ahead and took off the temporary bridge. I cleaned the remnant temp-bond from the teeth and dried them up, after which I took a bite registration by putting some JetBite polyvinylsiloxane material on a triple tray. I asked the patient to bite down gently on the tray and after waiting for 3 minutes I received my bite registration.

Afterward, we went ahead and took out the cavit G and a cotton roll from tooth #22 which will receive a post. I then took a yellow post system and tried it in the canal. I adjusted the yellow post system to the estimated height of the future permanent post and I placed some notches on it for retention during impression taking. Then we prepared a quadrant tray, and put some adhesive on it. I dried up the quadrant, put the yellow post system inside the canal of #22 trying to keep the post system parallel to the long axis of the tooth. Then I took some light body and syringed it around the yellow post system inside the canal of the tooth. As I was putting the light body around the post system, my assistant started putting Improgum on the quadrant tray, after which I took the tray with the Improgum and gently sat it in the patient’s mouth. The post system in the impression turned out to be parallel to the long axis of the tooth which enhanced the quality of our impression. The light body (in blue) covered the whole margin of the tooth and its close surrounding tissue.

After we were done with the impression, we irrigated the canal space of #22 with some saline, we put a cotton pellet inside the canal and covered it with Cavit G – this kept our root canal isolated from the oral environment. Then we took our temporary bridge and sat it back into the patient’s mouth. After making sure that the patient was comfortable with the temporary bridge, we dismissed the patient. 

R.F., New York University College of Dentistry, Patient 3

Categorised in: Dental Student Experiences

This post was written by Interns