Guided endodontics of calcified canals: The drilling path of rotary systems and intracanal dentin wear.

This study evaluated the drilling path (mm) and the dentin wear (mm 3 ) of two instruments used during guided endodontic access. Twenty mandibular incisors with calcified canals were selected using cone-beam computed tomography (CBCT) and fixed in articulated models. Preoperative CBCT scans were performed in combination with intraoral scanning, and the images were reconstructed in the Blue Sky Bio software for access planning and printing the guides. The access cavity was drilled with 1.0-mm-diameter bur (DSP) and 0.8-mm-diameter bur (Munce). Postoperative CBCT was performed, and the images obtained preoperative and postoperative were superimposed for the analyses. Data were analysed by a t-test and linear regression (α = 0.05). No difference was found in the drilling path (p = 0.422). However, the Munce bur had higher dentin wear than the DSP bur (p = 0.011). A positive linear correlation (R 2  = 0.859) was found between the factors.