How the heck does dental insurance work?

I called my insurance company buy the woman I talked to sounded really confused. If she's confused, how is that supposed to help out me?

I know it varies from plan to plan. Here is what I know so far:
I enjoy a $2500 maximum per calendar year.
I have an "80%/20%" plan (?)
My deductable is $300 (?)

Here is what I don't procure:

I went to the dentist, my bill be $306, my insurance paid for adjectives but $28 of it... if my deductable is $300, shouldn't I have to rate $300?

I do not understand the 80/20 entry, if I have a deductable too.

Anyone insurange brokers out at hand?

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Answers:   You should pay the first $300, and 20% of the remainder.

But near dental, there are some things that are covered, and some that aren't. Say you get a flouride treatment - that's usually not covere - you'd pay 100% of that.

But usually the cleaning and exam is covered within full, not subject to the deductible.

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The way it's supposed to work using your information - you pay the $300 deductible afterwards 20% of the remaining $6 ($1.20) for a total of $301.20.

Possible explainations (since we don't have the bill to look at or know your history next to this plan)

-your deductible is per lifetime and you've already paid contained by a different year.
-you've already paid bit of the deductible previously if the deductible is annual.
-the deductible may be per family instead of per creature.
-the insurance company may not have rewarded the amount to the dentist yet. Your bill is freshly an estimate of the charges and may change after the insurance company processes it.
-you may be on a DPO or DMO plan and the billed amount is smaller number than the actual charges because the insurance company will only allow rational and customary fees.

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