A patient presents with widespread ANUG (acute necrotizing ulcerative gingivitis) with necrotic papillae, fetid odor, and gray pseudomembranes. Which treatment should NOT be performed initially?

Correct answer: A. Biopsy

• A. Correct. Biopsy is NOT indicated for ANUG. ANUG has a characteristic clinical presentation (punched-out necrotic papillae, fetid breath, pain, fever in severe cases) that allows clinical diagnosis. Performing a biopsy is unnecessary, traumatic, and not the next step.
• B. Metronidazole is a first-line antibiotic for ANUG due to its activity against anaerobes (Treponema, Fusobacterium, Prevotella).
• C. Chlorhexidine rinse helps reduce the bacterial load in ANUG.
• D. Gentle debridement (SRP) is part of ANUG management after initial pain control.