Which would be considered the primary insurance company?

I asked a question earlier about dental insurance, but I forgot to add part 2. :) If I signed up right now with a Humana HMO dental plan, then in November I also enrolled in my husband's United Healthcare dental PPO plan, which one would be considered the primary insurance company?
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whichever you want.. you pick when you write them down on the form at the dental office. if it were my, i would pick the 1 with better coverage first, and the other as second. either way, the office will contact both insurance companies (or you if it's on you) to get your coverage.
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