Recent CommentsH&H Impression Technique: To Pack or Not To Pack?
posted in Fixed Prosthodontics, Cosmetic Dentistry, Impression Materials
« V-Ring: Easier Method for Achieving Tight Interproximal Contact? | Starfill 2B Dual Cure Composite: Any Suggestions? »
Print This Post
I recently started using the H&H impression technique for crown impressions. I bought the materials from J. Morita. I use Blue Velvet (bite registration type material) to make the initial impression. Than I do the second impression – the wash – using the Flexi Velvet, low viscosity material.
So far the crowns have fit great. I wait until the Blue Velvet has just started to set and then I have the patient open and I inject a small amount of the Flexi Velvet in the cervical area of the Blue Velvet impression and have the patient close. I am still packing cord. Some people who use this system do not pack cord. Does it still work if you do not pack cord?
>>Add Your Comment to This Post!
Get answers from experts in cosmetic dentistry to any question about your smile. IT'S FREE!
2 Responses to “ H&H Impression Technique: To Pack or Not To Pack? ”
Why would you pack cord? The main advantage of the technique is not to pack! First of all, allow the Blue Velvet to COMPLETELY SET and then dry the impresson and inject the wash material. The set Bleu Velvet forces the injection into the sulcus and forces OUT any fluids (blood)to give an excellent impression…that’s why it’s called hydraulic & hydrophobic. It works great and saves time and the patient is MUCH more comfortable for not having cord packed
I haven’t used retraction cord in 15 years. The stuff is the work of the devel. I use any regular PVS and a ridged sided stock tray. I prep the tooth (shoulder with bevel) then I have a heavy body impression of the prep. When it is set I remove and cut off any over flow and excess out side the tray. I Also cut any interprximal webbing that would make it difficult reincert the tray. Then I take a #4 para post drill and drill to holes into the prepped tooth from the buckle. I place the trayback over a dried prep and inject with a Coe syringe a light body material. You have to hold the try up or down so that it won’t rise up off the teeth. Out the hole comes any blood followed by saliva then clear impression material and you are done. If the margin i way deep sometimes I will plug the exit hole with an ammalgam condense the right size to plug the hole to build a little extra pressure. I remove the impression to check . I look for impression material on the occlusal surfaces of the other teeth. You don’t want that . It means you didn’t hold the tray down well enough and will through off you occlusion. You should have great flash into the sulcus . If you missed a spot, redrill the holes and inject again.This technique takes all the rush out multiple preps you just drill two hole in the buckle or facial of each prep and inject them one at a time.No rush to remove cord. My lab tells me the techie fight over my impressions because you can read a margin across the room. Not all my idea taken from a book on how to turn Hydrophobic into hydrophylic done 25 years ago. Can’t remember the Doctors name. Techique never fails in my hands.