In dental school I learned to take a denture impression by first creating the border molding in segments with red stick compound. Still a valid technique many of us use more modern materials today for taking impressions for full dentures. These are unique impressions and require different materials and techniques then for patients who have teeth. The first critical step is to use a tray specifically designed for the edentulous arch. Standard trays are too deep and the walls of the tray can become an impediment to getting a good impression.
I use VPS (Vinyl Polysiloxane) material for my denture impressions, both a heavy and a light body and utilize a two phase technique. The First step is always to select the correct size tray. Capturing the hamular notches, or retromolar pads requires good tray extension. Once the tray has been selected I load the tray with heavy body material and seat the tray. Try not to move your fingers around the tray, but pick one spot on each side and hold constant pressure. While the material is setting it is important to border mold by asking the patient to make specific movements and using your other hand. Continue to border mold until the material has set. Next I place a fast set light body material into the tray and reseat. Again, I border mold until the material has completed setting. Finally inspect the impression to make sure you have good vestibular extension without bubbles, and all the anatomic landmarks from that arch.
Maxillary Border Molding
- Have the patient open and close
- Have the patient move their mandible all the way right and than left
- Pull the left check down
- Pull the right cheek down
- Pull the upper lip down or have the patient stretch their upper lip down
Mandibular Border molding
- Have the patient stick out their tongue and toward the corners of their mouth
- Have the patient say “O” or suck in their cheeks
- Pull the right cheek up
- Pull the left cheek up
- Pull the patient slower lip upward