Accuracy and Healing Outcomes of Endodontic Surgery Using a Static Surgical Guide.

This prospective, single-arm, longitudinal clinical trial evaluates the accuracy and healing results of targeted endodontic surgery guided by 3D-printed static templates. The study aims to determine whether a fully digital workflow can standardize root-end resection, minimize bone removal, and provide favorable clinical outcomes.

Each eligible participant undergoes a standardized preoperative digital preparation. High-definition CBCT imaging data (DICOM format) and intraoral surface scan data (STL format) are acquired and imported into the Realguide software (version 5.0). After precise registration using three anatomical landmarks, the surgical path is planned. A virtual cylinder representing a 4.5-mm diameter trephine bur is positioned perpendicular to the root axis, calculated to achieve an exact 3-mm apicoectomy length. A teeth-supported static surgical guide with a 4.6-mm internal diameter sleeve and verification windows is then designed and fabricated using Stereolithography (SLA) 3D printing technology with biocompatible resin.

On the day of surgery, after administering local anesthesia (2% lidocaine with 1:100,000 epinephrine) and reflecting a full-thickness mucoperiosteal flap, the static surgical guide is securely positioned on the dental arch. Cortical plate osteotomy and root-end resection are executed in a single step through the guide sleeve using a 4.5-mm trephine bur at a speed of 800 rpm under continuous sterile saline irrigation. Following guide removal and periapical lesion debridement, a 3-mm deep retrograde cavity is prepared along the root canal axis using dedicated ultrasonic tips. The root end is then sealed with Well-Root PT bioceramic material, and the flap is secured using 5-0 nylon sutures. Postoperative medications including amoxicillin, ibuprofen, and paracetamol are prescribed uniformly.

Patient-centered outcomes (pain and swelling intensity) are self-recorded using a 6-point modified Visual Analog Scale (VAS) on days 1, 3, and 7 post-surgery. Sutures are removed at day 7. At the 6-month follow-up milestone, patients undergo comprehensive clinical evaluations based on the Gutmann & Harrison (1994) criteria. Concurrently, a postoperative CBCT scan is performed using identical exposure parameters to quantify periapical lesion volume reduction and grade structural bone healing (cortical plate, resection plane, and peri-radicular space regeneration) according to the Azim (2021) criteria. The cumulative digital data sets are superimposed to calculate the linear distance (mm) and angular deviations (degrees) between the planned and actual surgical paths, thereby establishing the structural accuracy of the static guided technique.