Impact of Mechanical Load of Three Post and Core Systems: CAD/CAM-fabricated Glassfiber, Prefabricated Glassfiber Customized with Composite Resin, and Cast Metal Posts and Cores

Abstract

ABSTRACT Aim and objective This study assessed the fracture resistance and failure mode frequencies in three post and core systems: CAD/CAM-fabricated glassfiber post and core, glassfiber post and core customized with composite resin, and cast metal post and core. Materials and methods After endodontic obturation and the post space preparation, 30 extracted mandibular premolars were distributed into three groups (n = 10): Group GFP: glassfiber post and core customized with composite resin, Group CPC: cast metal, and Group CAD/CAM: CAD/CAM-fabricated glassfiber post and core. All the specimens were luted with RelyX U200 cement, submitted to thermomechanical cycling, and then submitted to a compression test, applied at a 45° angle relative to the long axis of the tooth, until fracture. The fracture resistance data were submitted to ANOVA complemented by the Tukey test and the failure mode data by Fisher's exact test with the Freeman–Halton extension (α = 5%). Results There was no significant difference between the fracture resistance values found for groups CPC and CAD/CAM (p >0.05), and these values were significantly higher than those found for Group GFP (p < 0.05). In respect to failure mode frequencies, Group CAD/CAM had equal frequencies of adhesive and cohesive failures, Group GFP had exclusively cohesive failures in the composite core buildup, and Group CPC had 80% of cohesive failures in dentin vs 20% of adhesive failures (p < 0.001). Conclusion The fracture resistance of CAD/CAM-fabricated glassfiber posts and cores was comparable to that of cast posts and cores, and they were not associated with irreparable root fractures. Therefore, CAD/CAM-fabricated glassfiber posts and cores can be considered an effective method for restoring endodontically treated teeth. Clinical significance CAD/CAM system proved to be a viable alternative to cast posts and cores, since they were less associated with irreparable root fractures. How to cite this article Seckler INB, da Silveira Bueno CE, Kato AS, et al. Impact of Mechanical Load of Three Post and Core Systems: CAD/CAM-fabricated Glassfiber, Prefabricated Glassfiber Customized with Composite Resin, and Cast Metal Posts and Cores. Cons Dent Endod J 2020;5(2):36–41.