What dental insurance covers more and active immediately?

I really need to fix my teeth, root canal and fillings. Any good dental insurance plans?
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Delta and Blue Cross are good but each employer can pick and chose what is covered and how much. For instance, Cleanings, oral exams and x-rays may be covered at 100% but crowns only covered at 50%. The insurance company negotiates a price/coverage with each employer. They also decide when you are eligible. And watch out for the missing tooth clause: if the tooth is already missing they don't have to replace it.
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