Does the molding stuff they use to mold your teeth for braces cause you to vomit?

It may...: The impression material used may cause a gag reflex. This can be prevented by using less of it in the back of the tray, spraying the roof of the mouth with a topical numbing agent or better yet using a digital scan.

No & yes: It varies from person to person and on the practitioners abilities. The "gag reflex" varies but there are numerous techniques that can be employed to avoid the problem. One example that we use in our office is to use a warmer solution of water to add to the mixture. This makes the molding material set much more quickly in a patient who has an excessive "gag reflex" . This is just one method.

Techniques!: I haven't had a person regurgitate on me in the last 35 years and only twice in my career. There are so many techniques to avoid this. I use nitrous oxide\oxygen analgesia (sweet air\laughing gas) often, but the best technique is to count backwards by 3's to yourself starting from 100. (100, 97, 94, etc.) it has never failed me. It's also a matter of your dentist's technique.

Maybe: But the occurrence is pretty rare when you have impressions taken at an orthodontic office. We have taken so many impressions for people that the process is very routine and the odds are good you'll have no problems at all. If you're really anxious, make your appointment for first thing in the morning and wait to eat breakfast until after the impressions are taken.

Unlikely: My colleagues have all offered good tips 1. Wait on eating 2. Have them use warmer water/faster set impressions 3. I can't imagine using nitrous oxide, but ok... 4. Ask person taking it to seat the tray from back to front, so that any extra material flows out the front. 5. A quick spray of topical anesthetic helps.

Not usually: I've had it happen just 3 times in over 40 years. We orthodontists have gotten pretty good at making impression taking a relatively innocuous procedure. Schedule early in the day. Don't eat before your appointment. Take an Ibuprofen before you leave the house. Tell the orthodontist of your concerns and there are many things he can do to support you.

No: By itself it does not cause you to vomit. Some people do have a gag reflex when we take impressions, and yes, we occationally have someone vomit, but it is pretty rare (less than 1%). I suggest to close your eyes, wiggle your toes and try not to think about it-- it will be over in about 90 seconds. I have an easy gag reflex myself and hate impressions done on me, but it is bearable & over fast.