RESUMO
INTRODUCTION: Cone-beam computed tomographic (CBCT)-based 3-dimensional-printed surgical guides, such as those used in implant placement and orofacial surgery, allow for accurate planning and performance of surgical procedures. The objective of this study was to evaluate the accuracy of CBCT-designed surgical guides for use during endodontic surgery. METHODS: A split-mouth design was conducted using 48 roots in a cadaver model. In the experimental group, using information from the preoperative CBCT scans and digital impressions, surgical guides were designed using Blue Sky Bio (Grayslake, IL) planning software and printed using a Form 2 3-dimensional printer (Formlabs, Somerville, MA). The guides were designed to allow for surgical access at 3 mm from the apex of each root with depth control to the lingual or palatal surface of the root. In the control group, surgical access was completed "freehand" by visually approximating measurements from the CBCT scan only. The planned and postoperative CBCT images were superimposed, and the deviation of the surgical access point from the planned target was measured using Invivo software (Anatomage, San Jose, CA). A 2-tailed t test and the Fisher exact test were conducted to compare the deviation in the experimental CBCT-guided group versus the control CBCT-approximated freehand group. RESULTS: The mean deviation for the guided group (1.743 mm) was significantly less than that of the approximated freehand group (2.638 mm, P < .001). Only in 11 of the 24 samples of the control group was surgical access considered clinically successful (within the apical area of the root), whereas all 24 of the experimental samples were considered clinically successful. CONCLUSIONS: Using a CBCT-designed printed surgical guide is a more accurate method for access to the apical portion of the root during surgical endodontics compared with a "freehand" CBCT-approximated method.
