The most evident way for endodontic infection to occur is when the dental pulp is directly exposed to the oral cavity. The most frequent cause of pulp exposure is caries, however, trauma or iatrogenic restorative therapies can also expose the pulp directly to microorganisms. The oral bacteria from carious sores, saliva, or plaque that has accumulated on the exposed surface come into direct touch with the exposed pulp tissue. Exposed pulps almost always experience inflammation, necrosis, and infection. Although the amount of time between pulp exposure and canal-wide infection is uncertain, the process is typically gradual.