Can i rinse my mouth with oxygen peroxide if i just got composite veneers?

Hydrogen perox. ok: If you mean liquid hydrogen peroxide, yes. But not he concentrated versions used for whitening teeth, which will whiten your teeth but not the veneers, perhaps leaving you with a shade mismatch of your natural enamel and your veneers.

Yes: I assume you meant hydrogen peroxide. And as long as your gums are healthy, you can go ahead and rinse with it. If they aren't super healthy, that may be uncomfortable. Try warm salt water for the first few days.

Yes: To help the gums get healthy, of course, and make it peroxide and water half and half.

With restrictions: You can use 3% hydrogen peroxide mixed equally with water occasionally. I, like many other dentists do not recommend using it routinely on a daily basis long term.