The fracture strength of endocrowns manufactured from different hybrid blocks under axial and lateral forces

Abstract

Aim This in vitro study was conducted to compare the fracture strength of endocrowns manufactured from different hybrid blocks under axial and lateral forces. Material and methods Following root-canal treatment, 100 permanent mandibular first molars were randomly distributed among 5 groups according to restoration material. Endocrown restorations were produced from IPS e.max CAD (IPS), Vita Enamic (VE), GC Cerasmart (GC), Shofu (SH), and Brilliant Crios (BC) using CAD/CAM technology. Specimens were cemented, subjected to artificial aging, and further divided into 2 subgroups (n = 10) per group for fracture testing. Each specimen was placed on a universal testing machine and subjected to axial or lateral forces applied at a crosshead speed of 1 mm/min. Fracture data were analyzed using one-way ANOVA, Tukey, Tamhane T2, and Weibull tests. Results Statistically significant differences in fracture-strength (FS) values under axial and lateral forces were observed among the groups (P < 0.05). Group BC had the highest FS value under axial forces, whereas group IPS had the highest FS value under lateral forces. According to Weibull analysis, VE exhibited the highest reliability under axial forces (7.62), whereas IPS exhibited the highest reliability under lateral forces (4.68). No statistically significant differences were detected in the distribution of failure types under either axial or lateral forces among the groups (P > 0.05). Conclusion All of the hybrid blocks tested showed sufficient fracture strength for use as CAD/CAM-fabricated endocrowns. Clinical relevance Hybrid blocks can be used as an alternative to lithium disilicate blocks in endocrown restorations.

Endocrowns Clinical Performance and Patient Satisfaction: A Randomized Clinical Trial of Three Monolithic Ceramic Restorations

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Marginal Adaptation and Fracture Resistance of Endocrown Restorations Constructed From Two Cad/Cam Blocks.

“…Sample size calculated depending on a previous study (14) as a reference. According to this study, a sample size of 7 in each group has a 80% power to identify a difference between means of 77.59 with a significance level (alpha) of 0.05 (two-tailed).…”

Finite element and in vitro study on biomechanical behavior of endodontically treated premolars restored with direct or indirect composite restorations

“…Nowadays, in the era of minimally invasive dentistry, there has been a shift towards less invasive restorative solutions—Prevention of Extension instead of Extension for Prevention 10 . Resin composites and adhesive systems have improved immensely since their first introduction to the dental field 11 , 12 and can provide similar fracture resistance 13 – 15 and clinical survival 16 , 17 compared to indirect ceramic restorations. The advantage of composite restorations is their repairability and lower cost compared to the ceramic ones.…”