Comparison of two needle models in terms of bevel deformation during truncal block of the inferior alveolar nerve.

Objectives: To evaluate the differences in terms of bevel deformation between two types of needle of the same length and external caliber, but with different internal diameters, during truncal block of the inferior alveolar nerve.

Study Design: Four operators performed truncal block of the inferior alveolar nerve and infiltrating anesthesia of the buccal nerve for the extraction of a lower third molar in 266 patients. The truncal block was carried out using a standard 27G x 35 mm needle with an internal caliber of 0.