Micro-computerized tomographic analysis of premolars restored with oval and circular posts

Abstract

The purpose of the study was to evaluate by micro-computerized tomography (microCT) areas and volumes of post, cement, and voids/bubbles in the post space of oval-shaped premolars restored either with oval or circular posts. Twelve extracted premolars were divided into two groups according to the drill-fiber post system used: (1) GC Fiber Post Drill + circular post GC Fiber Post; (2) Ellipson tip(TM) + oval post Ellipson post(TM). Each tooth was scanned using microCT, and areas and volumes of canal, post space, post, cement, and voids at coronal, medium, and apical level were calculated by using a three-dimensional visualization software. Two-way analyses of variance and Tukey tests were used for statistical analysis (p lt 0.05). The area of voids was significantly greater at apical level of oval posts, but no difference was found between the levels among the groups. Regardless of post shape, the volume of voids and of cement was significantly higher at the coronal level. With oval posts, the total volume of cement was twice as much as with circular posts, and the difference was statistically significant. Our results indicate that the volume of voids does not depend on post shape. Moreover, the microCT analysis demonstrated that the volume of cement was greater with oval posts compared to circular posts. The microCT analysis provided interesting information on voids distribution and on the ratio between post shape and cement thickness. These results might address the clinician in the reconstruction of teeth with fiber posts.