I need to have a root canal done asap. It is really bad so says the dentist. Can I use both ins and a plan?

I have dental insurance and a dental plan. I just got dental insurance, and had a plan before. I don't know why they did not discover this earlier, anyway. My question is can I use my dental insurance for what they will cover and then the remaining balance out-of-pocket, use the plan for their percentage off? I contacted them, but they have not responded back yet. In their member handbook they said in some cases, but I was wondering if anyone knew if they have done this? What plan do you have? Thanks...
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No you cant use two plans, only one
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