Fracture Resistance of Endodontically Treated Roots with Oval Canals Restored with Oval and Circular Posts

• Oval posts and drills have been introduced. In the present study, root fracture after post space preparation and post placement using the oval system is proposed compared with the conventional system.
• The roots were endodontically treated, and the fracture strength was compared.
• Increasing information will increase the similarity of both academicians and clinicians regarding this issue.

IntroductionThe aim of the present study was to evaluate the effects of post space preparations with circular and oval post drills and the placement of oval and circular posts on the fracture strength of roots with oval canals.MethodsSeventy mandibular premolars with oval root canals were decoronated. Fourteen teeth were used as a control group (group 1), and the root canals of the remaining teeth were prepared up to size #30. The root canals were filled, and the samples were randomly divided into 4 experimental groups as follows: post space preparation with circular-shaped drills (group 2), post space preparation with oval-shaped drills (group 3), circular post placement (group 4), and oval post placement (group 5). A fracture strength test was performed on each specimen, and the data were statistically evaluated using 1-way analysis of variance and Tukey post hoc tests.ResultsThe fracture strengths of the circular posts–placed group were higher than those of the oval post–placed group (P < .001). The post space preparation using oval-shaped drills significantly decreased the fracture strength of the roots compared with the control group (P < .001).ConclusionsWithin the limitations of the present study, oval posts did not provide a higher fracture resistance to endodontically treated roots with oval canals compared with circular posts. Therefore, clinicians should be aware that oval posts are similar to circular posts in terms of enhancing the fracture resistance of roots with oval canals.