Reliability, failure probability, and strength of resin-based materials for CAD/CAM restorations.
This study investigated the Weibull parameters and 5% fracture probability of direct, indirect composites, and CAD/CAM composites.
Discshaped (12 mm diameter x 1 mm thick) specimens were prepared for a direct composite [Z100 (ZO), 3M-ESPE], an indirect laboratory composite [Ceramage (CM), Shofu], and two CAD/CAM composites [Lava Ultimate (LU), 3M ESPE; Vita Enamic (VE), Vita Zahnfabrik] restorations (n=30 for each group). The specimens were polished, stored in distilled water for 24 hours at 37°C. Weibull parameters (m= modulus of Weibull, σ0= characteristic strength) and flexural strength for 5% fracture probability (σ5%) were determined using a piston-on-three-balls device at 1 MPa/s in distilled water. Statistical analysis for biaxial flexural strength analysis were performed either by both one-way ANOVA and Tukey's post hoc (α=0.05) or by Pearson's correlation test.
Ranking of m was: VE (19.5), LU (14.5), CM (11.7), and ZO (9.6). Ranking of σ0 (MPa) was: LU (218.1), ZO (210.4), CM (209.0), and VE (126.5). σ5% (MPa) was 177.9 for LU, 163.2 for CM, 154.7 for Z0, and 108.7 for VE. There was no significant difference in the m for ZO, CM, and LU. VE presented the highest m value and significantly higher than ZO. For σ0 and σ5%, ZO, CM, and LU were similar but higher than VE.
The strength characteristics of CAD/ CAM composites vary according to their composition and microstructure. VE presented the lowest strength and highest Weibull modulus among the materials.
Faculty of Dentistry, National University of Singapore, Singapore.
Kiatlin
K
Lim
Faculty of Dentistry, National University of Singapore, Singapore.|JurongHealth Services, Department of Dentistry, Singapore.
Adrian U-Jin
AU
Yap
Faculty of Dentistry, National University of Singapore, Singapore.
Shruti Vidhawan
SV
Agarwalla
Faculty of Dentistry, National University of Singapore, Singapore.
Keson Beng-Choon
KB
Tan
Faculty of Dentistry, National University of Singapore, Singapore.
Vinicius
V
Rosa
D000704:Analysis of Variance; D003188:Composite Resins / Q000737:chemistry*; D017076:Computer-Aided Design; D019232:Dental Restoration Failure; D003793:Dental Restoration, Permanent / Q000379:methods*; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D018583:Pliability; D011336:Probability; D012016:Reference Values; D015203:Reproducibility of Results; D019279:Resin Cements / Q000737:chemistry*; D017640:Silicates / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry*; D013314:Stress, Mechanical; D013499:Surface Properties; D013718:Tensile Strength; D013997:Time Factors; D024505:Tocopherols / Q000737:chemistry*; D014082:Tooth Fractures; D015040:Zirconium / Q000737:chemistry*
C093075:3M Resin Cement; D003188:Composite Resins; D019279:Resin Cements; D017640:Silicates; C083568:Z100 composite resin; C574687:ceramage; D012822:Silicon Dioxide; D015040:Zirconium; D024505:Tocopherols