Periapical healing after root canal treatment
The periapical tissues undergo changes during the progression of dental caries. In case of extensive bacterial invasion involving the pulp, apical periodontitis is typically the body's host response. In response to the injury, chemotaxis occurs. After the initiation of inflammation, macrophages, leukocytes and lymphocytes enter and comprises the bulk of periodontitis. Necrotic tissue within the pulp chamber and canals provide nutrients for pathogenic bacteria to grow and form a periapical lesion.