Which of the following is NOT a test used for root canal therapy?

Digital imaging is not considered a direct test used for evaluating a tooth during root canal therapy. While it is an essential diagnostic tool that provides visual information about the tooth’s structure, the presence of decay, and the extent of infection, it does not assess the vitality or response of the pulp to specific stimuli in the way that the other tests do.

Percussion and palpation are clinical tests that help determine the health of the tooth by assessing pain responses, which indicate inflammation or other issues within the dental pulp. Thermal tests involve the application of hot or cold stimuli to gauge the tooth's response, specifically how the pulp reacts to temperature changes, which is critical in diagnosing the need for root canal therapy.

In contrast, digital imaging serves primarily as a supplementary method for confirming the diagnosis and guiding the treatment rather than being a test of pulp vitality or health.