Influence of access cavity design on the fracture resistance and root canal filling efficacy in simulated young permanent molars using cone-beam computed tomography: An in vitro study

Abstract

Aims: The aim of this study is to evaluate the influence of access cavity designs on the fracture resistance and root canal filling efficacy of simulated young permanent molars.Methodology: A total of seventy human unerupted impacted mandibular third molar teeth were collected. Ten were allocated as control; the remaining were designated as experimental, which were divided into three groups (20 each) based on access cavity design. All the samples were exposed to cone-beam computed tomography (CBCT) scanner before the access cavity preparation. Group I-The control group. Group IIa-traditional endodontic cavity (TEC), Group IIb-conservative endodontic cavity (CEC), Group IIc-ninja endodontic cavity (NEC). Endodontic access cavities were prepared and exposed to CBCT. Pre- and post-treatment percentage volumes of lost pericervical dentin were evaluated. Then the root canals were filled with calcium hydroxide and subjected to CBCT imaging for the evaluation of root canal filling efficacy. Evaluation of fracture resistance was carried out using a universal testing machine.Results: On observation, the volume of lost pericervical dentin was (14.8%) in TEC, (8.3%) in CEC and (6.8%) in NEC. There was no statistically significant difference (P > 0.05) between all the groups on root canal filling efficacy and the number of voids. Fracture resistance of the NEC and control group (P > 0.05) was greater compared to CEC and TEC.Conclusion: NEC is the accepted method that had better fracture resistance, with a minimum number of voids in the coronal and middle third of the root and had adequate apical seal compared to conservative and TECs.