A patient has a single round oral ulcer measuring 10 mm that has lasted over two weeks and may scar. By aphthous classification this is most consistent with a:

Correct answer: A. Major aphthous ulcer

• A. Correct. Major aphthae are large (>=10 mm), deep, long-lasting (weeks), and may heal with scarring.
• B. Minor aphthae are small (<10 mm), heal in 7-14 days without scarring.
• C. Herpetiform ulcers are numerous tiny (1-2 mm) clustered ulcers.
• D. A traumatic ulcer relates to an identifiable injury, not the aphthous pattern described.