Preventive
D1000-D1999

D1120Prophylaxis, Child

2026 Billing Guide ยท Last reviewed

A routine dental cleaning for child patients that removes plaque, calculus, and stains from primary or transitional teeth to prevent cavities and gum disease.

What This Code Covers

D1120 covers a routine dental cleaning (prophylaxis) for a child patient, typically under age 14, though some payers set different age cutoffs. The hygienist or dentist removes plaque, calculus, and stains from all tooth surfaces in the primary or transitional dentition, then polishes the teeth. This is a preventive service for children with healthy gums or mild gingivitis, not for children with periodontal conditions requiring therapeutic treatment.

Billing Guide

Bill this code when:

  • Child patient presents for a routine preventive cleaning
  • Patient is under the payer's age threshold for child prophylaxis (commonly under 14)
  • Patient has primary, mixed, or early transitional dentition
  • Cleaning is preventive in nature and includes scaling, polishing, and plaque removal

Do not bill this code when:

  • Patient meets the payer's age threshold for adult prophylaxis. Use D1110 instead
  • Patient has generalized gingival inflammation requiring scaling in the presence of moderate to severe inflammation. Consider D4346
  • Frequency limit for the benefit year has already been reached without documented medical necessity
  • The visit is limited to a fluoride application or exam only, with no actual prophylaxis performed

Insurance and Denial Prevention

Key Payer Rules:

  • Classified as preventive, typically covered at 100% in-network with no deductible
  • Most plans allow two child prophylaxis visits per benefit year, spaced at least six months apart
  • Medicaid programs vary by state but generally cover two per year for children
  • The age cutoff for D1120 vs. D1110 varies by payer. Common thresholds are age 13, 14, or the start of permanent dentition
  • D1120 and D1110 share frequency limitations and cannot both be billed in the same benefit period

Common Denials and How to Respond:

  • Upgraded to D1110 - Check the payer's specific age cutoff. If the patient falls under their child threshold, appeal with the patient's date of birth and a note on dentition status.
  • Frequency exceeded - Verify benefit year dates and prior cleaning dates. If the year has reset, resubmit with corrected dates. If the limit is genuinely met, the patient pays out of pocket.
  • Missing tooth chart or dentition status - Resubmit with documentation showing primary or mixed dentition. Include a note from the provider if the payer requires it.

Claim Submission Checklist

0/5 complete
Patient's date of birth to confirm age eligibility for child prophylaxis
Dentition status (primary, mixed, or transitional) noted in the record
Date of last prophylaxis to verify frequency compliance
Documentation of areas cleaned and methods used (hand scaling, polishing)
Any companion codes billed on the same visit (D0120, D1206, D1351)

Frequently Asked Questions

D1120 is the child prophylaxis code, used for patients under the payer's age threshold (often under 14). D1110 is the adult version of the same preventive cleaning. The clinical procedure is essentially the same, but payers separate them by patient age. Always check your specific payer's age cutoff because it is not standardized across all plans.

Yes. It is very common to bill D1120 alongside D1206 (fluoride varnish) on the same visit. Most payers allow both codes on the same date of service for children. Some plans bundle fluoride into the prophy benefit, so verify coverage before billing both.

D1120 is for a healthy child with no significant gingival disease. D4346 is for patients with generalized moderate to severe gingival inflammation but no periodontitis. If the child has visible inflammation, bleeding on probing across multiple sites, and heavy calculus, D4346 may be more appropriate. Document the clinical findings carefully to support whichever code you choose.

Keep This Handy

Save this D1120 reference for quick access during billing.

Codes commonly billed alongside or often confused with this procedure.