Can anyone define what is consider to be reasonable and necessary dental care?

I know I'm asking a question that judges, lawyers and congressmen can not answer, but I'm hoping someone out there will help before I am completely bankrupt.
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x-rays once a year, cleaning every 6 months and filings if needed. If your not able to afford this every 6 months then you go just once a year and have them take the x-rays every other year until your able to afford more. You only can do what you can afford... X-rays just shows more then they can see so if you have a cavity they can fix it.
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