Which of the following is primarily used to clean and widen the root canal?

Endo files are specialized instruments designed for use in root canal treatments. They are primarily utilized to clean and shape the canal space within a tooth. The unique design of endo files allows them to reach deep into the intricate anatomy of the root canal system, where they effectively remove infected or necrotic tissue and debris. The files vary in size and taper, enabling dentists to gently widen the canal as they work to create an appropriate shape for filling after disinfection.

During the root canal procedure, endo files are critical for achieving proper cleaning and shaping, which are essential to ensure that the canal is adequately prepared for subsequent steps, including disinfection and filling. This cleaning and shaping process helps to reduce the risk of infection and enhances the success of the endodontic treatment.

While the other instruments listed have their specific roles—such as an irrigating syringe for delivering disinfecting solutions, a Glick instrument for placing and shaping material, and Cavit for temporary fillings—they do not serve the same primary purpose of cleaning and widening the root canal as effectively as endo files do.