Influence of fatigue loading on fracture resistance of endodontically treated teeth restored with endocrowns

Purpose: This in vitro study aimed to evaluate the influence of fatigue loading on fracture resistance endodontically treated molars restored with endocrowns using different machinable blocks. Methods: Endodontically mandibular first were prepared a standardized method. Specimens divided into 4 groups (n = 10).Anatomically shaped manufactured VITA ENAMIC (VE) and KATANA Zirconia (KZ). Layered IPS e.max CAD (EM) BioHPP (BH). Half specimens each group subjected test, while other half thermocycling chewing simulation. After loading, loaded until failure. examined stereomicroscopy. Data analyzed ANOVA analysis variance Bonferroni post hoc test (?=0.05). Results: KZ had highest initial value (1810.20± 119.56 N) BH lowest (579.50± 76.15 N). The reduction after was significant for (1588.30±216.25 (502.60±11.53 non-significant VE (1101.70±77.05 EM (1112.10±74.12 Failure modes showed high percentage non-restorable fractures, restorable fractures. Conclusions: Within limitations this study, following can be concluded: Poly infiltrated ceramics should considered as proper material used an endocrown because its ability if failure occurred.