Which sequence describes inflammatory jaw lesions when the pulp is nonvital?

• A. Necrotic tissue → drainage into sinus tract → periapical inflammation (chemical mediators) → abscess/granuloma/cyst.
• B. Necrotic tissue → periapical inflammation (chemical mediators) → periapical abscess, granuloma, or cyst → drainage into sinus tract.
• C. Periapical inflammation → necrotic tissue → drainage into sinus tract → abscess.
• D. Drainage into sinus tract → necrotic tissue → periapical inflammation.

Answer: (A)

Nonvital pulp starts with necrotic tissue that serves as the source of infection. This triggers inflammatory activity in the surrounding periapical tissues, with chemical mediators and immune cells driving the response. A common response is to form a sinus tract, a drainage route that allows pus and inflammatory exudate to escape to the surface or oral mucosa. As the inflammatory process persists, the localized lesion can organize into an abscess, a granuloma, or a cyst, depending on how long the process lasts and how the tissue responds. So the sequence follows necrotic tissue → drainage through a sinus tract → periapical inflammation → abscess/granuloma/cyst, which reflects how drainage often accompanies ongoing inflammatory change before the final lesion becomes apparent.