(PR42) Static-guided versus Conventional Fiber Post Removal: A Pilot Study

Abstract: This in vitro study investigated the accuracy of a 3D-printed tooth-borne guide used to direct fiber post removal compared with a conventional freehand technique in extracted maxillary premolars. Eight extracted maxillary premolars with Vertucci type IV canal systems were used. After endodontic treatment and post space preparation, teeth were divided into two groups according to post removal technique. Teeth were mounted in custom printed resin models and scanned with CBCT before and after post cementation. CBCT data sets were imported into coDiagnostiX to design and print 3D tooth-borne guides with metal sleeves to direct instrumentation. All procedures were performed under a dental operating microscope and terminated when gutta percha was visualized or by operator choice. Postoperative CBCT scans were acquired. 3D images were segmented in Simpleware ScanIP and analyzed apical to the CEJ. The preoperative post volumes (P1) and the volumes of residual post were recorded (P2). The volumes of post removed (P1-P2) were calculated. Volumetric differences were evaluated using Welch’s t-test. The mean reduction in fiber post volume was 5.675mm3 in the guided group and 11.025mm3 using the conventional freehand technique, with a significant difference between groups (p=0.04). Fiber post removal with the aid of a 3D tooth-borne guide resulted in less post volume removal compared to a freehand technique. In this study, guided post removal was less accurate than the freehand control procedure.