"In sickness and in health, till death do us part," is in the wedding vows for a reason. He is supposed to support you and love you, and take care of you. He is NOT supposed to reject you just because you have some dental problems! Please, stop blaming yourself for him being so superficial.
If you sign up for an Instagram account, search there for videos about how to get Social Security disability. There are several attorneys on Instagram, who are giving excellent advice. I'm on disability, because I accidentally did what they had suggested! If only I had known the facts, I would have been a lot less nervous, and I would have been more successful sooner.
And while you are on Instagram, also run some searches for "emotional abuse." There are many, many women and psychologists on Instagram, who are posting videos to help women like you reclaim their self-worth after suffering emotional abuse from their husbands. (And that is exactly what you are experiencing.)
YOU are not the problem! You are a perfectly normal human being with a soul that just wants to be loved. Your husband is the problem, because he's too superficial to overlook minor cosmetic problems, and see the woman you really are.
You don't need to die, to get relief. You just need to find help, and find other people who are suffering like you. You can find them online; that's the positive side of social media. Please reach out...support is out there, and it doesn't cost one penny more than your internet connection. 💕