Exactly how does Dental insurance coverage work? Never had insurance before. Had medicaid, no insurance though?

I work at Wal-Mart and recently enrolled in their Dental Insurance. It doesn't kick in until January, so until then, I'm uninsured. Anyways, I get paid Bi-weekly and every pay check they take out $6.20 for the insurance, which isn't too bad at all. Anyways, I had Medicaid up until I was 18, then of course it was discontinued. How does dental insurance work? I know for certain things, it says you have to meet your annual deductible before coverage kicks in. What is that? On my handbook, it says the annual deductible is $50 for associates. So what if I have to have teeth filled or anything and the bill is like $800, what would my portion be? Also, with insurance, is it like a discount plan where you would have to pay your portion BEFORE the work is done or how does that all work?
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Typically most dental plans work as follows: If there is a deductible, you must pay that amount once a year before the plan will pay a part of the remaining charges. The plan usually has a maximum per year that it will pay towards your dental care. Usually that is between $2,000-$4,000 per year depending on the plan. Usually the plan will cover a certain percentage of your normal dental care (cleaning, fillings, etc.). That percentage is usually about 70%-80% of the cost. Usually plan will cover a smaller percentage of orthodontic or crowns (typically 50%). Usually the dentist will directly bill the insurance company for their share. Example: Plan has a $50 deductible, pays a maximum of $2,000 per year, pays 80% of normal dental work, and pays 50% for crowns. You have the following bill for work done at the dentist over a period of several days. Exam: $40 Cleaning: $100 Filling: $300 Crown $900 Deductible: $50 Plan pays 80% of $390 or $312 Plan pays 50% of $900 or $450 Plan pays a total of $762 Your cost to the dentist is $578 ($50 + $78 + $450) Plan will pay up to $1238 more towards your dental treatment during the rest of the year. The dentist may bill you before you leave his office after each visit or may bill you later. If you can't afford to pay your share when you receive the bill, you should find a dentist that will accept payments. If you have normal work (cleaning, fillings, etc.), the amount you pay will be relatively small but when crowns are down, you generally pay quite a bit. Some plans also pay 100% for the exam and cleaning.
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