J Adv Prosthodont.  2016 Feb;8(1):30-36. 10.4047/jap.2016.8.1.30.

Influence of the preparation design and artificial aging on the fracture resistance of monolithic zirconia crowns

• Mitov G
• Anastassova-Yoshida Y
• Nothdurft
• von See C
• Pospiech P

• KMID: 2393193
• DOI: http://doi.org/10.4047/jap.2016.8.1.30

Abstract

PURPOSE
The aim of this study was to evaluate the fracture resistance and fracture behavior of monolithic zirconia crowns in accordance with the preparation design and aging simulation method.
MATERIALS AND METHODS
An upper first molar was prepared sequentially with three different preparation designs: shoulderless preparation, 0.4 mm chamfer and 0.8 mm chamfer preparation. For each preparation design, 30 monolithic zirconia crowns were fabricated. After cementation on Cr-Co alloy dies, the following artificial aging procedures were performed: (1) thermal cycling and mechanical loading (TCML): 5000 cycles of thermal cycling 5degrees C-55degrees C and chewing simulation (1,200,000 cycles, 50 N); (2) Low Temperature Degradation simulation (LTD): autoclave treatment at 137degrees C, 2 bar for 3 hours and chewing simulation; and (3) no pre-treatment (control group). After artificial aging, the crowns were loaded until fracture.
RESULTS
The mean values of fracture resistance varied between 3414 N (LTD; 0.8 mm chamfer preparation) and 5712 N (control group; shoulderless preparation). Two-way ANOVA analysis showed a significantly higher fracture loads for the shoulderless preparation, whereas no difference was found between the chamfer preparations. In contrast to TCML, after LTD simulation the fracture strength of monolithic zirconia crowns decreased significantly.
CONCLUSION
The monolithic crowns tested in this study showed generally high fracture load values. Preparation design and LTD simulation had a significant influence on the fracture strength of monolithic zirconia crowns.

Keyword

Ceramics; Zirconia; In vitro; Tooth preparation; CAD-CAM

MeSH Terms

Aging*
Alloys
Cementation
Ceramics
Computer-Aided Design
Crowns*
Mastication
Molar
Tooth Preparation
Alloys
Ceramics

Figure

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  Fig. 1 Preparation designs used in the study: overlay of scans of the three different preparation designs.

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  Fig. 2 Monolithic zirconia crown, cemented on the metal die with resin socket. (A) Vestibular view. (B) Occlusal view: semi-anatomical occlusal design.

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  Fig. 3 Fracture loads (N) of the different test groups.

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  Fig. 4 SEM image of a fracture surface: crack origin is on the inner side of the crown.

Reference

1. Raigrodski AJ. Contemporary materials and technologies for all-ceramic fixed partial dentures: a review of the literature. J Prosthet Dent. 2004; 92:557–562.

2. Tinschert J, Natt G, Mohrbotter N, Spiekermann H, Schulze KA. Lifetime of alumina- and zirconia ceramics used for crown and bridge restorations. J Biomed Mater Res B Appl Biomater. 2007; 80:317–321.

3. Manicone PF, Rossi Iommetti P, Raffaelli L. An overview of zirconia ceramics: basic properties and clinical applications. J Dent. 2007; 35:819–826.

4. Sundh A, Molin M, Sjogren G. Fracture resistance of yttrium oxide partially-stabilized zirconia allceramic bridges after veneering and mechanical fatigue testing. Dent Mater. 2005; 21:476–482.

5. Coelho PG, Silva NR, Bonfante EA, Guess PC, Rekow ED, Thompson VP. Fatigue testing of two porcelain-zirconia all-ceramic crown systems. Dent Mater. 2009; 25:1122–1127.

6. Heintze SD, Rousson V. Survival of zirconia- and metal-supported fixed dental prostheses: a systematic review. Int J Prosthodont. 2010; 23:493–502.

7. Swain MV. Unstable cracking (chipping) of veneering porcelain on all-ceramic dental crowns and fixed partial dentures. Acta Biomater. 2009; 5:1668–1677.

8. Taskonak B, Borges GA, Mecholsky JJ, Anusavice KJ, Moore BK, Yan J. The effects of viscoelastic parameters on residual stress development in a zirconia/glass bilayer dental ceramic. Dent Mater. 2008; 24:1149–1155.

9. McLaren EA, White SN. Glass-infiltrated zirconia/alumina based ceramic for crowns and fixed partial dentures. Pract Periodontics Aesthet Dent. 1999; 11:985–994.

10. Goodacre CJ, Campagni WV, Aquilino SA. Tooth preparations for complete crowns: an art form based on scientific principles. J Prosthet Dent. 2001; 85:363–376.

11. Fenske C, Jarren MP, Sadat-Khhonsari MR. Fracture strength of full ceramic crowns in dependence of the preparation width. Dtsch Zahnarztl Z. 1999; 54:732–734.

12. Meier M, Fischer H, Richter EJ, Maier HR. Influence of different preparation forms on the fracture resistance of full-ceramic molar crowns. Dtsch Zahnarztl Z. 1995; 50:295–299.

13. Beuer F, Edelhoff D, Gernet W, Naumann M. Effect of preparation angles on the precision of zirconia crown copings fabricated by CAD/CAM system. Dent Mater J. 2008; 27:814–820.

14. Vult von Steyern P. All-ceramic fixed partial dentures. Studies on aluminum oxide- and zirconium dioxide-based ceramic systems. Swed Dent J Suppl. 2005; (173):61–69.

15. Kern M. Clinical long-term survival of two-retainer and single-retainer all-ceramic resin-bonded fixed partial dentures. Quintessence Int. 2005; 36:141–147.

16. Ghazal M, Kern M. The influence of antagonistic surface roughness on the wear of human enamel and nanofilled composite resin artificial teeth. J Prosthet Dent. 2009; 101:342–349.

17. Kobayashi K, Kuwajima H, Masaki T. Phase change and mechanical properties of ZrO₂-Y₂O₃ solid electrolyte after aging. Solid State Ionics. 1981; 3:489–493.

18. Chevalier J, Cales B, Drouin JM. Low temperature aging of Y-TZP ceramics. J Am Ceram Soc. 1999; 82:2150–2154.

19. Lughi V, Sergo V. Low temperature degradation -aging- of zirconia: a critical review of the relevant aspects in dentistry. Dent Mater. 2010; 26:807–820.

20. Ardlin I. Transformation-toughened zirconia for dental inlays, crowns and bridges: chemical stability and effect of low-temperature aging on flexural strength and surface structure. Dent Mater. 2002; 18:590–595.

21. Papanagiotou HP, Morgano SM, Giordano RA, Pober R. In vitro evaluation of low-temperature aging effects and finishing procedures on the flexural strength and structural stability of Y-TZP dental ceramics. J Prosthet Dent. 2006; 96:154–164.

22. Kim JW, Covel NS, Guess PC, Rekow ED, Zhang Y. Concerns of hydrothermal degradation in CAD/CAM zirconia. J Dent Res. 2010; 89:91–95.

23. Deville S, Chevalier J, Dauvergne C, Fantozzi G, Bartolome JF, Moya JS, Torrecillas R. Microstructural investigation of the aging behavior of (3Y-TZP)-Al₂O₃ composites. J Am Ceram Soc. 2005; 88:1273–1280.

24. Snyder MD, Hogg KD. Load-to-fracture value of different all-ceramic crown systems. J Contemp Dent Pract. 2005; 6:54–63.

25. Lang NP. Periodontal considerations in prosthetic dentistry. Periodontol. 2000; 9:118–131.

26. Preis V, Schmalzbauer M, Bougeard D, Schneider-Feyrer S, Rosentritt M. Surface properties of monolithic zirconia after dental adjustment treatments and in vitro wear simulation. J Dent. 2015; 43:133–139.

27. Akar GC, Pekkan G, Cal E, Eskitascioglu G, Ozcan M. Effects of surface-finishing protocols on the roughness, color change, and translucency of different ceramic systems. J Prosthet Dent. 2014; 112:314–321.

28. Kou W, Molin M, Sjogren G. Surface roughness of five different dental ceramic core materials after grinding and polishing. J Oral Rehabil. 2006; 33:117–124.

29. Monasky GE, Taylor DF. Studies on the wear of porcelain, enamel, and gold. J Prosthet Dent. 1971; 25:299–306.

30. Oh WS, Delong R, Anusavice KJ. Factors affecting enamel and ceramic wear: a literature review. J Prosthet Dent. 2002; 87:451–459.

31. Kosmac T, Oblak C, Jevnikar P, Funduk N, Marion L. The effect of surface grinding and sandblasting on flexural strength and reliability of Y-TZP zirconia ceramic. Dent Mater. 1999; 15:426–433.

32. Rosentritt M, Behr M, van der Zel JM, Feilzer AJ. Approach for valuating the influence of laboratory simulation. Dent Mater. 2009; 25:348–352.

33. DeLong R, Douglas WH. An artificial oral environment for testing dental materials. IEEE Trans Biomed Eng. 1991; 38:339–345.

34. Krejci I, Reich T, Lutz F, Albertson M. In-vitro test method for evaluation of dental restorations. Schweiz Monatsschr Zahnmed. 1990; 100:8–12.

35. Teoh SH, Ong LF, Yap AU, Hastings GW. Bruxing-type dental wear simulator for ranking of dental restorative materials. J Biomed Mater Res. 1998; 43:175–183.

36. Gale MS, Darvell BW. Thermal cycling procedures for laboratory testing of dental restorations. J Dent. 1999; 27:89–99.

37. Senyilmaz DP, Canay S, Heydecke G, Strub JR. Influence of thermomechanical fatigue loading on the fracture resistance of all-ceramic posterior crowns. Eur J Prosthodont Restor Dent. 2010; 18:50–54.

38. Lee JK, Kim H. Surface crack initiation in 2Y-TZP ceramics by low temperature aging. Ceram Int. 1994; 20:413–418.

39. Lance MJ, Vogel EM, Reith LA, Cannon RW. Low-temperature aging of zirconia ferrules for optical connectors. J Am Ceram Soc. 2001; 84:2731–2733.

40. Zhenglan L, Danyu J, Lei H, Guoqiang Z, Qiang L, Cheng Z. Low temperature degradation of yttria stabilized zirconia. Key Eng Mater. 2007; 336-338:1188–1189.