After completing pulp extirpation, debridement and placing a dressing; apical periodontitis is because:
A. Over instrumentation extending into periapical area
B. Irritation from chemicals used
C. Entrapped bacteria
D. One or any combination of the above
A. Over instrumentation extending into periapical area
B. Irritation from chemicals used
C. Entrapped bacteria
D. One or any combination of the above