The Fracture Resistance of Zirconia Based Dental Crowns from Cyclic Loading: A Function of Relative Wear Depth
This in vitro study focused on investigating the fatigue resistance of veneered zirconia molar crowns with different veneering ceramic thicknesses, simulating the relative wear depths under simulated cyclic loading. A mandibular first molar was prepared and then scanned using computer-aided design/computer-aided manufacturing (CAD/CAM) technology to fabricate 32 zirconia copings of uniform 0.5 mm thickness. The manufactured copings then veneered with 1.5 mm, 1.0 mm, 0.5 mm, and 0.0 mm representing 0%, 33%, 66%, and 100% relative wear of a normal ceramic thickness of 1.5 mm. All samples were thermally aged to 6000 thermo-cycles for 2 minutes with distilled water between 5 ˚C and 55 ˚C. The samples subjected to cyclic fatigue and fracture testing using SD Mechatronik chewing simulator. These samples are loaded up to 1.25x10⁶ cycles or until they fail. During fatigue, testing, extensive cracks were observed in samples with 0.5 mm veneering layer thickness. Veneering layer thickness 1.5-mm group and 1.0-mm group were not different in terms of resisting loads necessary to cause an initial crack or final failure. All ceramic zirconia-based crown restorations with varying occlusal veneering layer thicknesses appeared to be fatigue resistant. Fracture load measurement for all tested groups before and after fatigue loading exceeded the clinical chewing forces in the posterior region. In general, the fracture loads increased after fatigue loading and with the increase in the thickness of the occlusal layering ceramic.
Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1317380Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 693
 F. Zarone, S. Russo and R. Sorrentino, “From porcelain fused to metal to zirconia: Clinical and experimental considerations,” Dental Materials, vol. 27, pp. 83-96, 2011.
 C. J. Goodacre, G. Bernal, K. Rungcharassaeng, and J.Y. Kan, “Clinical complications in fixed prosthodontics,” J. Prosthet Dent., vol. 90, no. 1, pp. 31-41, 2011.
 P. C. Guess, S. Schultheis, E. A. Bonfante, PG. Coelho, J. L. Ferencz, and N.R. Silva, “all –ceramic systems: laboratory and clinical performance,” Dent. Clin. North Am., vol. 55, no., 2, pp. 333–335, 2011.
 B. Al-Amleh, K. Lyons, and M. Swain, “Clinical trials in zirconia: a systematic review,” Journal of Oral Rehabilitation, vol. 37, no. 8, pp. 641-652, 2010.
 H. Choa, H. Wona, and H. Choeb, et al. “Fracture Characteristics of Dental Ceramic Crown according to Zirconia Coping Design,” Procedia Engineering, vol. 10, pp. 1561–1566, 2011.
 A. E. Bianchi, Bosetti, M. Dolci, Jr., MT. Sberna, F. Sanfilippo, and M. Cannas, “In vitro and in vivo follow-up of titanium transmucosal implants with a zirconia collar,” Journal of Applied Biomaterials & Biomechanics, vol. 2, pp. 143–150, 2004.
 T. Kosmac, C. Oblak, P. Jevnikar, N. Funduk, and L. Marion, “The effect of surface grinding and sandblasting on flexural strength and reliability of Y-TZP zirconia ceramic,” Dental Materials, vol. 15, pp. 426-433, 1999.
 P. Christel, A. Meunier, and M. Heller, et al., “Mechanical properties and short-term in vivo evaluation of yttrium-oxide-partially-stabilized zirconia,” J. Biomed Mater Res., vol. 23, no. 1, pp. 45–61, 1989.
 R. Belli, J. Coutinho, U. Lohbauer, and L. Baratieri, “On the brittleness of dental ceramics: why do they fail, Quintessence publishing co., 2010.
 P. K. Dawson, “Evaluation, diagnosis, and treatment of occlusal problems,” 2d ed. St Louis: Mosby, 1989.
 B. Stewart, “Restoration of the severely worn dentition using systemized approach for a predictable prognosis,” J. Periodont Rest Dent., vol. 18, pp. 47-57, 1998.
 C. Goodacre, V. Wayne, B. Campagni, and A. Steven, “Aquilino. Tooth preparations for complete crowns: An art form based on scientific Principles,” J. Prosthet Dent., vol. 85, pp. 363-376, 2001.
 P. C. Guess, R. A. Zavanelli, N. R. Silva, E. A., P. G. Coelho and V. P. Thompson, “Monolithic CAD/CAM lithium disBonfante ilicate versus veneered Y-TZP crowns: comparison of failure modes and reliability after fatigue,” J. Prosthodont, vol. 23, no. 5, pp. 434-442, 2010.
 F. Beuer, M. Stimmelmayr, and JF. Gueth, et al., “In vitro performance of full-contour zirconia single crowns,” Dent Mater., vol. 28, no. 4, pp. 449-56, 2012.
 W. S. Lin, C. Ercoli, C. Feng, and D. Morton, “The effect of core material, veneering porcelain, and fabrication technique on the biaxial flexural strength and weibull analysis of selected dental ceramics,” J. Prosthodont., vol. 21, no. 5, pp. 353-62, 2012.
 M. T. Yucel, I. Yondem, F. Aykent, and O. Eraslan, “Influence of the supporting die structures on the fracture strength of all-ceramic materials,” Clin. Oral Investig., vol. 16, no. 4, pp. 1105-1110, 2012.
 J. Park, J. Chang, J. Ferracane, and B. Lee, “How should composite be layered to reduce shrinkage stress: Incremental or bulk filling?,” Dental Materials, vol. 24, no. 11, pp. 1501–1505, 2008.
 A. J. Raigrodski, M. B. Hillstead, G. K. Meng, and K. H. Chung, “Survival and complications of zirconia-based fixed dental prostheses: a systematic review,” J. Prosthet Dent., vol. 107, no. 3, pp. 170-177, 2012.
 I. Sailer, J. Gottnerb, S. Kanelb, and C.H. Hammerle, “Randomized controlled clinical trial of zirconia-ceramic and metal-ceramic posterior fixed dental prostheses: a 3-year follow-up,” J. Prosthodont., vol. 22, no. 6, pp. 553-60, 2009.
 N. Wakabayashi, K. J. Anusavice, “Crack initiation modes in bilayered alumina/porcelain disks as a function of core/veneer thickness ratio and supporting substrate stiffness,” J. Dent. Res., vol. 79, no. 6, pp. 1398-1400, 2000.
 A. Sundh, and G. Sjögren, “A comparison of fracture strength of yttrium-oxide- partially-stabilized zirconia ceramic crowns with varying core thickness shapes and veneer ceramics,” J. Oral Rehabil., vol. 31, no. 7, pp. 682-688, 2004.
 A. Shirakura, H. Lee, A. Geminiani, C. Ercoli, and C. Feng, “The influence of veneering porcelain thickness of all ceramic and metal ceramic crowns on failure resistance after cyclic loading,” J. Prosthet. Dent., vol. 101, no. 2, pp. 119-127, 2009.