How does my Canadian health insurance and dental cards work?

I live in Ontario and I got the first permanent job in my life, so I finally have benefits for once, but I don't know how to use my health insurance and dental insurance. Do I have to pay up front then get compensated later, or will the insurance be able to immediately take care of the cost of trips to the dentist or doctor? I'm hoping the cost can be taken care of right away because I can't afford to pay for expensive visits to the dentis up front, even if I will get the money back later. How much does the average dental check up cost in Canada because I haven't been to one since I was a teenager? I need new glasses, so would this be covered under my insurance too? Thanks for any info, preferably from fellow Canadians.
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Its going to depend. My employer and my wife's employer both use the same company. However the policies both companies have are different with regards to payouts. Trips to the doctor should be covered by OHIP. Most plans will not cover optometrist visits. For the dentist give your card to their admin, they can figure it out. My policy pays for their portiion of the coverage right away and I only have to pay for the remainder on the spot. My wife's plan she has to pay 100% at the dentist, but the covered amount is direct deposited to her bank in 1-2 business days. Most dentists take credit cards now. Check your plan formulary for eyeglass coverage. My plan has $0 coverage and my wife's is $200 every two years. (You'd think a tech company would have eyeglass coverage since 80% of the staffing complement is nerds) The dentist is going to try and get you to do a full set of xrays and possibly two cleanings if you don't regularly floss (there might be a lot of build up). You might be looking at $300 in the Toronto area.
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