Medical Deductions. I just realized I can claim what extended plans didn't cover for Braces. How far back can I include on this years taxes? 3 kids worth to maybe claim.

You can claim medical expenses within a one year period that ends in 2018. So depending on what your other expenses are and when you paid for the braces, you might be able to claim your 2017 costs in 2018. However, you can also go back and adjust your previous year’s returns to include the braces expenses. Here’s how you can make changes after you have filed your tax return: https://turbotax.community.intuit.ca/replies/2647992