Endodontics · patient case question
Which inflammatory cell predominates in a lesion that has been draining intermittently for two years?
Patient case: The Pimple That Comes and Goes
Patient: 52-year-old female
Chief Complaint: “There’s a pimple on my gum that comes and goes. It’s been almost two years.”
Background: Healthy, no medications. Describes intermittent swelling that drains, subsides for weeks, then recurs. Minimal pain throughout.
Medications: None
Vital Signs: BP 124/78 mmHg · HR 72 bpm · RR 16 · T 98.4°F
Findings: Tooth #14 has no restoration and has never received endodontic treatment. It gives no response to cold and is not tender to percussion. A well-defined periapical radiolucency is present, and a gutta-percha point placed in the sinus tract tracks radiographically to the apex of #14. Separately, tooth #29 has a fractured lingual cusp. Tooth #17 is horizontally impacted and its crown contacts the distal root of #18, which shows a concave radiolucent defect at the point of contact.
Show answer and explanation
Correct answer: B. Lymphocytes and plasma cells
- A. Incorrect. Basophils are rare in tissue and are associated with immediate hypersensitivity reactions.
- B. Correct. Chronic inflammation is characterized by mononuclear cells — lymphocytes, plasma cells, and macrophages. The plasma cells produce the antibody that reflects sustained antigenic stimulation from bacteria in the canal system, and this pattern defines a lesion of long duration.
- C. Incorrect. Neutrophils dominate acute inflammation and appear in the first hours to days. They are certainly present within the purulent exudate itself, but they do not characterize a two-year lesion.
- D. Incorrect. Eosinophils are prominent in parasitic infection and allergic disease, not in chronic bacterial periapical inflammation.
Note: Read the question stem carefully. If it asks about the purulent exudate itself, the answer is neutrophils. If it asks about the chronic lesion overall, the answer is lymphocytes and plasma cells.