Paying a medical provider to remove wisdom teeth is deductible as a medical expense. It is deductible in the year paid. If you charged it to a credit card, it is considered payed in the year the charge was entered.
Medical expenses are an itemized deduction. Only the amount of expenses in excess of 10% of your AGI (7.5% if 65 or older) are deductible. You only get a tax benefit if the total of all your itemized deductions is more than the standard deduction.