DxCodebookFY2027 · Oct 1, 2026 – Sep 30, 2027

Category · FY2027

K04 Diseases of pulp and periapical tissues

  • Header · not billable

K04 is not billable. The category heads 12 billable codes in FY2027, grouped under 10 subdivisions.

Index → code

Where it sits

  1. Chapter 11 Diseases of the digestive system (K00-K95)
  2. K00-K14 Diseases of oral cavity and salivary glands (K00-K14)
  3. K04 Diseases of pulp and periapical tissues
Billable codes
12
Subdivisions
10
CC / MCC codes
3 / 0
HCC V28 codes
0
New FY2027
0
Index entries
98

Codes in K04

  1. K04.0
    Pulpitis
    Header
    Inclusion terms 2

    Inclusion terms

    • Acute pulpitis
    • Chronic (hyperplastic) (ulcerative) pulpitis
  2. K04.01
    Reversible pulpitis
    BillableCC
  3. K04.02
    Irreversible pulpitis
    BillableCC
  4. K04.1
    Necrosis of pulp
    Billable
    Inclusion terms 1

    Inclusion terms

    • Pulpal gangrene
  5. K04.2
    Pulp degeneration
    Billable
    Inclusion terms 3

    Inclusion terms

    • Denticles
    • Pulpal calcifications
    • Pulpal stones
  6. K04.3
    Abnormal hard tissue formation in pulp
    Billable
    Inclusion terms 1

    Inclusion terms

    • Secondary or irregular dentine
  7. K04.4
    Acute apical periodontitis of pulpal origin
    BillableCC
    Inclusion terms 1, Excludes1 1

    Inclusion terms

    • Acute apical periodontitis NOS

    Excludes1

    • acute periodontitis (K05.2-) K05.2
  8. K04.5
    Chronic apical periodontitis
    Billable
    Inclusion terms 2, Excludes1 1

    Inclusion terms

    • Apical or periapical granuloma
    • Apical periodontitis NOS

    Excludes1

    • chronic periodontitis (K05.3-) K05.3
  9. K04.6
    Periapical abscess with sinus
    Billable
    Inclusion terms 2

    Inclusion terms

    • Dental abscess with sinus
    • Dentoalveolar abscess with sinus
  10. K04.7
    Periapical abscess without sinus
    Billable
    Inclusion terms 2

    Inclusion terms

    • Dental abscess without sinus
    • Dentoalveolar abscess without sinus
  11. K04.8
    Radicular cyst
    Billable
    Inclusion terms 3, Excludes2 1

    Inclusion terms

    • Apical (periodontal) cyst
    • Periapical cyst
    • Residual radicular cyst

    Excludes2

    • lateral periodontal cyst (K09.0) K09.0
  12. K04.9
    Other and unspecified diseases of pulp and periapical tissues
    Header
  13. K04.90
    Unspecified diseases of pulp and periapical tissues
    Billable
  14. K04.99
    Other diseases of pulp and periapical tissues
    Billable

CC/MCC: as a secondary diagnosis, unless the principal diagnosis is on the code’s PDX exclusion list (MS-DRG v44 Appendix C; list on the code card).

Sources of each column.

Instructions

Notes that also apply

Chapter 11 instructions (Excludes2 8): printed on the chapter 11 page.

Index entries

  • Endodontitis → K04.01
  • Odontomyelitis (closed) (open) → K04.01
  • Pulpitis (acute) (anachoretic) (chronic) (hyperplastic) (putrescent) (suppurative) (ulcerative) → K04.01
  • Putrescent pulp (dental) → K04.1
  • Denticles (pulp) → K04.2
  • Gumboil → K04.7
  • Parulis → K04.7
  • Devitalized tooth → K04.99
  • Nonvital, nonvitalized tooth → K04.99
  • Pulpless tooth → K04.99
  • Abscess (connective tissue) (embolic) (fistulous) (infective) (metastatic) (multiple) (pernicious) (pyogenic) (septic)pulp, pulpal (dental) → K04.01
  • Endodontitisreversible → K04.01
  • Odontomyelitis (closed) (open)reversible → K04.01
  • Polyp, polypusdental → K04.01
  • Polyp, polypuspulpal (dental) → K04.01
  • Pulpitis (acute) (anachoretic) (chronic) (hyperplastic) (putrescent) (suppurative) (ulcerative)reversible → K04.01
  • Endodontitisirreversible → K04.02
  • Odontomyelitis (closed) (open)irreversible → K04.02
  • Pulpitis (acute) (anachoretic) (chronic) (hyperplastic) (putrescent) (suppurative) (ulcerative)irreversible → K04.02
  • Gangrene, gangrenous (connective tissue) (dropsical) (dry) (moist) (skin) (ulcer)pulpal (dental) → K04.1
  • Gangrene, gangrenous (connective tissue) (dropsical) (dry) (moist) (skin) (ulcer)tooth (pulp) → K04.1
  • Necrosis, necrotic (ischemic)dental pulp → K04.1
  • Necrosis, necrotic (ischemic)pulp (dental) → K04.1
  • Calcificationdental pulp (nodular) → K04.2
  • Calcificationpulpal (dental) (nodular) → K04.2
  • Change(s) (in) (of)dental pulp, regressive → K04.2
  • Change(s) (in) (of)regressive, dental pulp → K04.2
  • Degeneration, degenerativedental pulp → K04.2
  • Degeneration, degenerativepulp (tooth) → K04.2
  • Stone(s)pulpal (dental) → K04.2
  • Abnormal, abnormality, abnormalitieshard tissue formation in pulp (dental) → K04.3
  • Anomaly, anomalous (congenital) (unspecified type)hard tissue formation in pulp → K04.3
  • Dentinirregular (in pulp) → K04.3
  • Dentinsecondary (in pulp) → K04.3
  • Irregular, irregularitydentin (in pulp) → K04.3
  • Secondarydentin (in pulp) → K04.3
  • Septicteeth, tooth (pulpal origin) → K04.4
  • Granulomaapical → K04.5
  • Granulomadental → K04.5
  • Granulomaperiapical → K04.5

58 more, longer entries are not listed; the search box finds them by word.

NCHS Alphabetic Index. Index first, then the Tabular List.

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