Fracture Resistance of Endodontically Treated Teeth Restored with Direct and Indirect Biomimetic Techniques: An In-vitro Study

Author : Basma Fayad ,Hala Fayek Khalil, Fatma Makkeyah, Islam Mohamed Heiba

Abstract :Introduction: Conventional full-coverage restorations for endodontically treated teeth often necessitate excessive tooth reduction, particularly in structurally intact cases. Aim: This in vitro study compared fracture resistance and failure modes of endodontically treated molars restored with biomimetic approaches using bioceramic sealers: direct short fiber-reinforced composite (SFRC) versus indirect 3D-printed hybrid composite endocrowns. Materials and Methods: Thirty-six intact human mandibular second molars were equally divided into three groups (n=12): Group A received a standardized endodontic treatment then restored with direct SFRC restoration (everX Posterior), Group B received a standardized endodontic treatment then restored with indirect endocrowns (Permanent Crown Resin) cemented with self-adhesive resin cement (RelyX Unicem), and Group C served as intact controls without endodontic treatment. specimens underwent thermal cycling (20,000 cycles, 5-55°C) before fracture testing in a universal testing machine. Failure modes were categorized as restorable, possibly restorable, or non-restorable. Results: Statistical analysis employed ANOVA with Tukey HSD post-hoc tests for load values and chi-square for failure modes (α=0.05). Results demonstrated significantly higher fracture resistance in Group B (2180.33±142.15N) compared to Group A (1941.63±135.62N) and Group C (1254.00±98.34N) (p<0.001). However, Group A exhibited significantly more restorable fractures (48.7%) versus Groups B (10%) and C (16.1%) (p<0.01). While 3D-printed endocrowns showed superior load-bearing capacity, direct SFRC restorations demonstrated more favorable failure modes Conclusion: Material selection should consider both fracture resistance and reparability potential when employing biomimetic approaches for endodontically treated molars.

Keywords :Endodontically treated molars, fracture resistance, SFRC, 3D-printed endocrowns, biomimetic restoration Ask ChatGPT

Conference Name :International Conference on Dentistry and Dental Materials (ICDDM-25)

Conference Place Madrid, Spain

Conference Date 14th Jul 2025