I received an excellent tip from another dentist regarding impression-taking techniques. He suggests that with the automix impression material guns you first bleed the material from the two cartridges, attach the mixing syringe tip, and then "again" extrude at least one inch of material before syringing intraorally around the tooth. Of course, this needs to be completed just prior to taking the impression. The assistant can do this while the dentist is removing the retraction cord.

Thank you for the great tip. Most dentists bleed the material before the tip is attached but the second time may be the key.

Are there any other hints out there on taking a great impression? If you know any, please send them in.

Here are a few hints from me:

1) Remember to always pack retraction cord. Don't expect the impression material to do that for you. I like to use a small cord, like Gingibraid size 0.

2) Do not attempt an impression in an inflamed and bleeding gingival field. It may be smarter to place a well-fitting temporary and treat the inflammation first with a chlorhexidine mouth rinse for a week or two before impression taking.

3) Remember that latex gloves will inhibit the set of impression material if touched. Wear vinyl gloves for impressioning and to not handle the material. If you have contaminated the prepped tooth with a gloved hand, swab the tooth with a cotton pellet dipped in water and/or hydrogen peroxide.

4) Impression material needs to be supported around the tooth. In most cases, this may be better accomplished with the use of a quad tray instead of a triple tray. This is especially true in the mandibular posterior where the tongue exerts a lateral pressure. Also, remember the tray adhesive needs to be applied at least 20 minutes prior to impressioning.

5) Last, but not least, remember to allow the impression material to fully set in the mouth. Use a "timer" and relax. It's your time to rest and the extra seconds in the mouth can make your crown a success!