Farklı Üretim Tekniği ve Materyaller Kullanılarak Üretilen Estetik Post-Kor Sistemlerinin Kırılma Dayanıklılığının iIn Vitro Olarak İncelenmesi

Abstract

The choice of an appropriate restoration for endodontically treated anterior teeth is guided by strength and esthetics. Ceramic posts and cores present an esthetic option as foundation restorations for ceramic crowns. The purpose of this in vitro study was to evaluate fracture strength of four different esthetic post and core systems. Forty maxillary central incisors received endodontic treatment and were divided into 4 groups (n=10) as follows: 1-piece milled zirconium oxide post and core (Lava Zr), 1-piece milled Lava Ultimate post and core (Lava Ultimate), prefabricated zirconium oxide post with heat-pressed ceramic core (Cosmo-IPS), prefabricated fiber post with composite resin core (Fiber- Composite). The posts and cores were cemented with dual-polymerized composite resin cement (RelyX Unicem). Zirconium oxide copings were made for each specimen, and cemented. After cementation of copings to core structures, 6000 thermal cycles (5-55 ?C) applied and all specimens were tested to failure with the static load applied 45 degree angled to the tooth axis with Universal testing machine. Mean fracture strength of test groups 1, 2, 3 and 4 is respectively 378 N, 334 N, 481 N, 385 N. One way ANOVA was used to determine the differences among fracture strength scores, with statistical significance at p<0.05. When p-values from One way ANOVA were significant, the post hoc Tukey HSD test was used to determine factors affect difference. Cosmo-IPS group?s specimens recorded statistically significantly higher load-to-failure values when compared Lava Ultimate group. All posts and core systems evaluated presented sufficient mean load-to-failure values for anterior tooth restorations including the new suggested post and core material LavaTM Ultimate CAD/CAM Restorative.