Effect of Ceramic Veneering on the Microstructure of Pre-sintered Cobalt-Chromium, Compared to Pre-sintered Zirconia and Conventional Cast Alloys
Microstructural analysis of Presintered CoCr
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Abstract
Objectives: We aimed to evaluate ceramic-alloy interface and emphasize the alteration of alloy microstructure after ceramic layering.
Materials and Methods: Thirty-two discs made from a ceramic-alloy combination of pre-sintered cobalt-chromium (CoCr), cast CoCr, cast nickel-chromium (NiCr), or pre-sintered zirconia were prepared with eight discs in each group. Four specimens were examined as manufactured and four were ceramic-layered. Scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-Ray diffractometer (XRD), and an atomic force microscope were used for analysis. Non-layered specimens received ceramic fire-heating without adding any ceramic. Alloy microstructure was compared before and after ceramic veneering or heating within the same group. Mean differences in grain size and surface roughness were compared among groups. P<0.05 was considered significant.
Results: SEM showed a close bonding interface between alloys and ceramics. EDX demonstrated differences compared to the manufacturer’s composition. Ceramic-layering reduced grain size for both milled alloys (P<0.05), whereas grain size increased in cast groups (P=0.011). Heat treatment did the same for the CoCr groups (P=0.013). Ceramic veneering increased the surface roughness of the cast CoCr (Gi) (P=0.029) and NiCr (Wi) (P=0.005) groups, whereas zirconia roughness average (Ra) showed a slight decrease (P=0.282). XRD showed no differences among zirconia, NiCr, and milled CoCr groups before and after veneering. Crystallite size differed between monoclinic and tetragonal phases in zirconia.
Conclusion: The study highlights that ceramic-layering induces significant microstructural changes in alloys, enhancing bonding potential and mechanical stability. Pre-sintered materials show a fine homogeneous surface, optimizing ceramic adherence and potentially improving clinical outcomes.
2. DIN E. 22674 (2006): Dentistry–Metallic materials for fixed and removable restorations and appliances. DIN-Taschenbuch.;267(1):524-53.
3. Anusavice KJ, Ringle RD, Fairhurst CW. Bonding mechanism evidence in a ceramic--nonprecious alloy system. J Biomed Mater Res. 1977 Sep;11(5):701-9.
4. Guess PC, Kulis A, Witkowski S, Wolkewitz M, Zhang Y, Strub JR. Shear bond strengths between different zirconia cores and veneering ceramics and their susceptibility to thermocycling. Dent Mater. 2008 Nov;24(11):1556-67.
5. Li KC, Ting S, Prior DJ, Waddell JN, Swain MV. Microstructural analysis of Co-Cr dental alloy at the metal-porcelain interface: A pilot study. NZ Dent. J. 2014 Dec;1(110):138-42.
6. Takaichi A, Suyalatu, Nakamoto T, Joko N, Nomura N, Tsutsumi Y, et al. Microstructures and mechanical properties of Co-29Cr-6Mo alloy fabricated by selective laser melting process for dental applications. J Mech Behav Biomed Mater. 2013 May;21:67-76.
7. Podrez-Radziszewska M, Haimann K, Dudziński W, Morawska-Sołtysik M. Characteristic of intermetallic phases in cast dental CoCrMo alloy. Archives of foundry engineering. 2010;10(3):51-6.
8. Hallmann L, Ulmer P, Reusser E, Louvel M, Hämmerle CH. Effect of dopants and sintering temperature on microstructure and low temperature degradation of dental Y-TZP-zirconia. J Eur Ceram Soc. 2012 Dec 1;32(16):4091-104.
9. Tholey MJ, Swain MV, Thiel N. Thermal gradients and residual stresses in veneered Y-TZP frameworks. Dent Mater. 2011 Nov;27(11):1102-10.
10. Tholey MJ, Berthold C, Swain MV, Thiel N. XRD2 micro-diffraction analysis of the interface between Y-TZP and veneering porcelain: role of application methods. Dent Mater. 2010 Jun;26(6):545-52.
11. Inokoshi M, Yoshihara K, Nagaoka N, Nakanishi M, De Munck J, Minakuchi S, et al. Structural and Chemical Analysis of the Zirconia-Veneering Ceramic Interface. J Dent Res. 2016 Jan;95(1):102-9.
12. Ozkomur A, Ucar Y, Ekren O, Arai Shinkai RS, Teixeira ER. Characterization of the interface between cast-to Co-Cr implant cylinders and cast Co-Cr alloys. J Prosthet Dent. 2016 May;115(5):592-600.
13. Hallmann L, Ulmer P, Wille S, Kern M. Effect of differences in coefficient of thermal expansion of veneer and Y-TZP ceramics on interface phase transformation. J Prosthet Dent. 2014 Sep;112(3):591-9.
14. Daou EE, Özcan M, Salameh P, Al-Haj Husain N, Salameh Z. Comparison of Adhesion of a Novel Pre-sintered Cobalt-Chromium to Pre-sintered Zirconia and Cast Nickel-Chromium. J Contemp Dent Pract. 2018 Jul 1;19(7):816-823.
15. Daou EE, Ounsi H, Özcan M, Al-Haj Husain N, Salameh Z. Marginal and internal fit of pre-sintered Co-Cr and zirconia 3-unit fixed dental prostheses as measured using microcomputed tomography. J Prosthet Dent. 2018 Sep;120(3):409-414.
16. Al Jabbari YS, Koutsoukis T, Barmpagadaki X, Zinelis S. Metallurgical and interfacial characterization of PFM Co-Cr dental alloys fabricated via casting, milling or selective laser melting. Dent Mater. 2014 Apr;30(4):e79-88.
17. Revilla-León M, Al-Haj Husain N, Methani MM, Özcan M. Chemical composition, surface roughness, and ceramic bond strength of additively manufactured cobalt-chromium dental alloys. J Prosthet Dent. 2021 May;125(5):825-831.
18. Al Jabbari YS. Physico-mechanical properties and prosthodontic applications of Co-Cr dental alloys: a review of the literature. J Adv Prosthodont. 2014 Apr;6(2):138-45.
19. Rosentritt M. A focus on zirconia : an in-vitro lifetime prediction of zirconia dental restorations. PhD thesis Universiteit Amsterdam; 2008.
20. Vásquez VZ, Ozcan M, Kimpara ET. Evaluation of interface characterization and adhesion of glass ceramics to commercially pure titanium and gold alloy after thermal- and mechanical-loading. Dent Mater. 2009 Feb;25(2):221-31.
21. International Organization for Standardization. 4287-Geometrical Product Specifications (GPS)-Surface Texture: Profile Method-Terms, Definitions and Surface Texture Parameters; International Organization for Standardization: Geneva, Switzerland, 1997
22. MacDonald MJ, Vorberger J, Gamboa EJ, Drake RP, Glenzer SH, Fletcher LB. Calculation of Debye-Scherrer diffraction patterns from highly stressed polycrystalline materials. J. Appl. Phys.. 2016 Jun 7;119(21).
23. Lu Y, Wu S, Gan Y, Li J, Zhao C, Zhuo D, et al. Investigation on the microstructure, mechanical property and corrosion behavior of the selective laser melted CoCrW alloy for dental application. Mater Sci Eng C Mater Biol Appl. 2015 Apr;49:517-525.
24. Takaichi A, Suyalatu, Nakamoto T, Joko N, Nomura N, Tsutsumi Y, et al. Microstructures and mechanical properties of Co-29Cr-6Mo alloy fabricated by selective laser melting process for dental applications. J Mech Behav Biomed Mater. 2013 May;21:67-76.
25. Culha O, Zor M, Gungor MA, Arman YU, Toparli M. Evaluating the bond strength of opaque material on porcelain fused to metal restorations (PFM) alloys by scratch test method. Materials & Design. 2009 Sep 1;30(8):3225-8.
26. Venkatachalam B, Goldstein GR, Pines MS, Hittelman EL. Ceramic pressed to metal versus feldspathic porcelain fused to metal: a comparative study of bond strength. Int J Prosthodont. 2009 Jan-Feb;22(1):94-100.
27. Hong JM, Razzoog ME, Lang BR. The effect of recasting on the oxidation layer of a palladium-silver porcelain alloy. J Prosthet Dent. 1988 Apr;59(4):420-5.
28. Wu Y, Moser JB, Jameson LM, Malone WF. The effect of oxidation heat treatment of porcelain bond strength in selected base metal alloys. J Prosthet Dent. 1991 Oct;66(4):439-44.
29. Johnson T, van Noort R, Stokes CW. Surface analysis of porcelain fused to metal systems. Dent Mater. 2006 Apr;22(4):330-7.
30. Hong MH, Lee DH, Hanawa T, Kwon TY. Comparison of microstructures and mechanical properties of 3 cobalt-chromium alloys fabricated with soft metal milling technology. J Prosthet Dent. 2022 Mar;127(3):489-496.
31. Kappert H, Eichner K. In: Eichner K, ed Dental materials and their processing. 5th ed, Huthig, Heidelberg. 2005;1988;1:77-86
32. Durand JC, Jacquot B, Salehi H, Fages M, Margerit J, Cuisinier FJ. Confocal Raman microscopic analysis of the zirconia/feldspathic ceramic interface. Dent Mater. 2012 Jun;28(6):661-71.
33. Tsuruki J, Kono H, Okuda Y, Noda M, Arikawa H, Kanie T,Ban S. Factors affecting on the bond strength of dental zirconia to veneering porcelains. Key Eng Mater 2013; 529-530: 507-511.
34. Durand JC, Jacquot B, Salehi H, Margerit J, Cuisinier FJ. Confocal Raman microscopy and SEM/EDS investigations of the interface between the zirconia core and veneering ceramic: the influence of a liner and regeneration firing. J Mater Sci Mater Med. 2012 Jun;23(6):1343-53.
| Issue | Vol 21 (Continuously Published Article-Based) | |
| Section | Original Article | |
| DOI | https://doi.org/10.18502/fid.v21i32.16362 | |
| Keywords | ||
| Dental Materials Materials Testing Zirconium | ||
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