Assessment of Canker Sores (Recurrent Aphthous Stomatitis)

Initial Clinical Assessment

• The American Academy of Oral Medicine recommends documenting the exact date when the ulcer first appeared and tracking its progression 1
• The International Journal of Oral Science suggests assessing pain severity and impact on eating, drinking, and speaking 1
• The British Journal of Dermatology recommends asking about fever, malaise, or prodromal illness 3
• The International Journal of Oral Science advises noting if pain is disproportionate to the size of the lesion 1
• The International Journal of Oral Science recommends documenting gastrointestinal symptoms: abdominal pain, diarrhea, or blood in stool 1, 2

Laboratory Investigations

• The International Journal of Oral Science suggests performing full blood count to screen for anemia, leukemia, or neutropenia 2
• The Praxis Medical Insights recommends coagulation studies to exclude biopsy contraindications 8
• The International Journal of Oral Science advises fasting blood glucose to identify hyperglycemia 2
• The MMWR Recommendations and Reports recommends HIV antibody testing 7
• The Praxis Medical Insights suggests syphilis serology testing 8

When to Perform Biopsy

• The International Journal of Oral Science recommends biopsy for any ulcer persisting >2 weeks without clear diagnosis 1, 2
• The Praxis Medical Insights advises biopsy for ulcers not responding to 1-2 weeks of appropriate treatment 5
• The International Journal of Oral Science suggests biopsy for atypical features: irregular borders, induration, or fixation to underlying tissue 2

Red Flags Requiring Urgent Evaluation

• The International Journal of Oral Science recommends urgent evaluation for ulcers >2 weeks duration 1, 2
• The International Journal of Oral Science advises urgent evaluation for indurated or fixed ulcers 1
• The International Journal of Oral Science suggests urgent evaluation for painless ulcers 1
• The MMWR Recommendations and Reports recommends urgent evaluation for unilateral cervical lymphadenopathy 7
• The British Journal of Dermatology advises urgent evaluation for constitutional symptoms: fever, weight loss, or night sweats 3