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K04.4

K04.4Acute apical periodontitis of pulpal origin

Billable / specific codeICD-10-CM

K04.4 is a billable, specific ICD-10-CM code for acute apical periodontitis of pulpal origin. It is valid for submission on a claim.

Excludes1 — never code together

These conditions cannot occur together. Billing both on the same encounter is a denial.

  • acute periodontitis (K05.2-)

Inclusion terms

Alternative wordings a physician may use in the chart for this same code.

  • Acute apical periodontitis NOS

Other codes that can never be billed with K04.4

These codes carry an Excludes1 note pointing at K04.4. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading K04.4 alone.

  • K05.2Aggressive periodontitis

Risk adjustment

K04.4 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.

How K04.4 is indexed

Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to K04.4.

  • Septicteeth, tooth(pulpal origin)
  • Periodontitisapicalacute(pulpal origin)

Related codes at this level

Codes that share K04. If K04.4 is not quite right, the correct code is usually one of these.

Questions about K04.4

Is K04.4 a billable ICD-10-CM code?
Yes. K04.4 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does K04.4 sit in the tabular list?
Diseases of the digestive system (K00-K95), in the block Diseases of oral cavity and salivary glands (K00-K14).
What cannot be coded together with K04.4?
K04.4 carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.
ICD-10-CMFY2026-Apr· effective April 1, 2026

Loaded directly from the CMS/NCHS ICD-10-CM public-domain release — see data sources and our editorial policy. If this page disagrees with the CMS tabular list, this page is wrong. Reference information for professional coders; not medical or billing advice.