Waiting period for dental services?

I have a PPO dental plan and there are waiting periods for certain procedures. Is this waiting period from the time the insurance starts or from the time the proposed procedure is recommended? For example my son needs braces and there is a 12 month waiting period, is that 12 months from the time the insuance started or 12 months from the time the ortho says he needs braces? Do I have to notify the insurance company prior or just wait the 12 months?
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You should call the insurance company to make sure. Always take down the date and who you talked to just to cover all your bases. Different companies have different plans, so your best just giving them a call.
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