It depends on your filing status and the total deductions you have.
You deduct either the total of your itemized deductions, or the Standard Deduction for your filing status. Check the chart below to find your Standard Deduction based on your filing status.
You can deduct the portion of your medical and dental expenses that exceeds 7.5% of your AGI, so you will see that figure when you start the section. It'll say something like Do your medical and dental expenses exceed $2,400? Answer Yes to continue.