My mom won't let me fix my cavity help please!?

I found out I had a little cavity in my rear right molar in June. I have dental insurance, but every time I ask my mom when I can fix it before it becomes big, she says, "You should have taken better care of your teeth!" And I have a wisdom tooth growing right next to it that needs removal too! What can I do to stop it from becoming a big, painful cavity as I go off to college tomorrow? Or to convince her to let me get it fixed?
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If she has dental insurance, and is not letting you use it for dental work,. when you need it, this is called child abuse. When you are 18 she has no more responsibility for you. Colleges usually have medical centers, but looking at her and saying THIS HURTS DO SOMETHING might help. Pretend that it does. I do not know what to tell you, but I am glad I am not in your position.
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