Medical Deduction

In 2023 I incurred a $6,000 dental expense. The cost was covered by a financial institution associated with the dental office.  I will have monthly payments. As of October, 2023, I had only made one payment, but will make additional monthly payments the remainder of 2023. When I file my taxes for 2023, can I use the entire $6,000 as a medical expenditure, or only the amount of payments I made in 2023.  Thx.