Skip to main content

N37 Remark Code: Missing or Invalid Tooth Number

N37 means the tooth number or letter on the claim was missing, incomplete, or invalid. For dental procedures performed on a specific tooth, the payer needs a valid tooth designation to adjudicate the line.

Quick facts

Code
N37 (RARC N37)
Status
Active In use since January 1, 2000; last modified February 28, 2003.
Code set
Remittance Advice Remark Codes (RARC)
Group codes
  • CO (Contractual Obligation): The line is denied as a correctable data error. It is not billable to the patient while it can be fixed.
  • PI (Payer Initiated Reduction): Some government dental programs report the same issue as a payer-initiated adjustment.
Official description
Missing/incomplete/invalid tooth number/letter.
X12 Remittance Advice Remark Codes, retrieved September 25, 2026
Last verified
against the official X12 list.

What N37 means

A dental claim line for a tooth-specific procedure must say which tooth was treated. The payer uses that designation to check history (was this tooth already restored or extracted?), frequency limits, and whether the procedure makes sense for that tooth. N37 means the payer could not use the tooth number or letter you reported, either because it was blank, formatted incorrectly, or not a valid designation.

N37 almost always travels with CARC 16. It is a data problem, not a coverage decision.

Common causes

  • The tooth number field was left blank on a tooth-specific procedure.
  • A permanent tooth number was entered for a primary tooth, or the reverse.
  • The practice used a different numbering system (for example, a two-digit international notation) instead of the Universal system.
  • Leading zeros, spaces, or extra characters were included.
  • The procedure was performed on a supernumerary tooth and reported in a non-standard way.

How to fix it

  1. Check the clinical chart for the tooth treated and whether it is primary or permanent.
  2. Enter the correct designation in the tooth number field on the ADA dental claim form or the corresponding field in the electronic dental claim.
  3. Confirm related fields, such as surfaces, match the tooth.
  4. Submit a corrected claim according to the payer’s process for dental resubmissions.

How to prevent it

Configure your practice management software to require a tooth number for procedures that need one, and to validate that the designation matches the patient’s dentition. Keep charting and billing linked so the tooth recorded clinically carries directly onto the claim.

Codes that may appear with N37

  • CO-16 (Claim/service lacks information or has submission/billing error(s).): The claim is missing information; N37 identifies the tooth designation.
  • N39 (Procedure code is not compatible with tooth number/letter.): A tooth number was reported, but the procedure is not compatible with it.
  • N75 (Missing/incomplete/invalid tooth surface information.): The tooth surface information is missing or invalid.
  • N384 (Records indicate that the referenced body part/tooth has been removed in a previous procedure.): Records show the referenced tooth was removed in an earlier procedure.
  • N849 (Missing Tooth Clause: Tooth missing prior to the member effective date.): A missing tooth clause applies because the tooth was missing before coverage began.

N37 FAQ

Which tooth numbering system should I use?

In the United States, dental claims generally use the Universal system: numbers 1 through 32 for permanent teeth and letters A through T for primary teeth. Use what the payer specifies.

Do all dental procedures need a tooth number?

No. Procedures like exams or full-mouth imaging do not. Tooth-specific procedures, such as restorations, extractions, and crowns, do, and some procedures use an area of the mouth or quadrant instead.

What about supernumerary teeth?

Supernumerary teeth have their own designations in the Universal system. Check the payer's claim instructions for the exact format.