Start practicing

Pathology · patient case question

Each of the following can cause interproximal staining EXCEPT:

Patient case: Sjögren Syndrome and Blood Pressure Screening

demo: 56-year-old female

chief: “My mouth and eyes are constantly dry.”

history: Rheumatoid arthritis. Positive anti-SSA (Ro) and anti-SSB (La) antibodies.

meds: Hydroxychloroquine

findings: Blood pressure 145/92 mmHg on two readings. Dry, atrophic oral mucosa with a lobulated tongue, generalized gingival recession, marginal gingivitis, and rampant cervical caries. Bilateral parotid enlargement. Extensive interproximal staining.

  1. Chlorhexidine rinse
  2. Chromogenic bacteria
  3. Tetracycline
  4. Iron supplements
Show answer and explanation

Correct answer: C. Tetracycline

  • A. Chlorhexidine is a well-recognized cause of extrinsic brown staining, worst in interproximal and stagnation areas.
  • B. Chromogenic bacteria produce black or green extrinsic stain, particularly along the gingival margin and interproximally.
  • C. Correct — this is the exception. Tetracycline produces intrinsic discoloration by chelating with calcium during tooth development, giving banded grey-brown staining through the whole tooth — not surface interproximal stain.
  • D. Iron supplements produce black extrinsic staining on tooth surfaces.

Practice Pathology questions Pathology study notes

More Pathology practice questions