The purpose of this research was to evaluate how differing endodontic access cavity geometries influence canal transportation (CT) and centering ability (CA) in mandibular molars when employing the Bondent Platinum File System, as assessed via cone-beam computed tomography (CBCT). 30 extracted human permanent mandibular molars that satisfied the inclusion criteria were randomly assigned to one of three groups: Group 1 (TEC): Traditional endodontic access cavity (control), Group 2 (CEC): Conservative endodontic access cavity, and Group 3 (TrEC): Truss endodontic access cavity. The specimens underwent initial CBCT scanning before being randomly allocated into the three groups. Mechanical preparation of the root canals was performed with the Bondent platinum file system, using a #25.06 file in the mesiobuccal and mesiolingual canals and a #30.06 file in the distal canal. Post-instrumentation CBCT imaging was performed to measure CT and CA at apical distances of 3, 5, and 7 mm. The data were evaluated through one-way analysis of variance followed by Tukey’s post hoc test. Statistically significant differences (P < 0.01) in both mean CT and CA were recorded when comparing Group 1 (TEC) against Groups 2 (CEC) and 3 (TrEC). Dentin removal peaked at 3 mm, decreased at 5 mm, and was lowest at 7 mm. The distal canal suffered the most pronounced dentin loss relative to the remaining canals. Minimally invasive access cavity configurations (CEC and TrEC) were associated with lower CT and superior CA compared to the traditional design (TEC). The authors acknowledged study limitations, noting that conservative access geometries yield reduced deviation (CT) and enhanced centering of instrumented canals compared with the traditional technique (TEC). These outcomes suggest the potential benefits of integrating less-invasive access cavity designs into clinical endodontics to improve therapeutic outcomes.
