through your mouth or nose?

breathing thru mouth a lot can lead to more decay I think.

bad breath too...
...

If you breathe more frequently through your mouth, you are inhaling more dust and particles in the air, which get caught in your mouth. Having crap caught in your mouth isn't always a good thing. If you breathe through your nose, they are trapped and caught by your nasal system.

Have never had a Dentist ask that. Something new?

Your saliva contains special substances that protect and repair your teeth. It also serves to wash away bacteria. People who breathe through their mouth or have dry mouths don't get the full protection of saliva for their teeth. This can lead to more decay and cavities.

Sometimes we also ask this because it is important for you to be able to breathe through your nose if you are going to get some forms of sedation (like laughing gas).

I believe your dentist is some sort of weirdo and wants to do something to you while you are knocked out. I would report this type of strange behavior.

9 times out of 10 if your breathing through your mouth during your examination you are steaming up their mirror and they cant see... plus it can cause a drier mouth which could lead to the saliva not working to its best to wash away debris which could lead to caries in the long run.

i guess if you breath through your mouth it would effect you mouth in someway so they want to know