The effect of abrading and cutting instruments on machinability of dental ceramics
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The aim was to investigate the effect of machining instruments on machinability of dental ceramics. Four dental ceramics, including two zirconia ceramics were machined by three types (SiC, diamond vitrified, and diamond sintered) of wheels with a hand-piece engine and two types (diamond and carbide) of burs with a high-speed air turbine. The machining conditions used were abrading speeds of 10,000 and 15,000 r.p.m. with abrading force of 100 gf for the hand-piece engine, and a pressure of 200 kPa and a cutting force of 80 gf for the air-turbine hand-piece. The machinability efficiency was evaluated by volume losses after machining the ceramics. A high-abrading speed had high-abrading efficiency (high-volume loss) compared to low-abrading speed in all abrading instruments used. The diamond vitrified wheels demonstrated higher volume loss for two zirconia ceramics than those of SiC and diamond sintered wheels. When the high-speed air-turbine instruments were used, the diamond points showed higher volume losses compared to the carbide burs for one ceramic and two zirconia ceramics with high-mechanical properties. The results of this study indicated that the machinability of dental ceramics depends on the mechanical and physical properties of dental ceramics and machining instruments.
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Conflict of interest
The authors declare that they have no conflict of interest.
- 5.Kontonasaki E, Kantiranis N, Papadopoulou L, Chatzistavrou X, Kavouras P, Zorba T, Sivropoulou A, Chrissafis K, Paraskevopoulos KM, Koidis PT. Microstructural characterization and comarative evaluation of physical, mechanical and biological properties of three ceramics for metal-ceramic restrations. Dent Mater. 2008;24:1362–73.CrossRefGoogle Scholar
- 7.International Organization for Standardization. ISO 6872: Dental ceramic. Geneva, Switzerland; 2008.Google Scholar
- 8.International Organization for Standardization. ISO 9693: Metal-ceramic dental restorative systems. Geneva, Switzerland; 1999.Google Scholar
- 10.Kern M, Sasse M, Wolfart S. Ten-year outcome of three-unit fixed dental prostheses made from monolithic lithium disilicate ceramic. J Am Assoc. 2012;143:234–40.Google Scholar
- 12.Sax C, Hämmerle CH, Sailer I. 10-year clinical outcomes of fixed dental prostheses with zirconia frameworks. Int J Comput Dent. 2011;14:183–202.Google Scholar
- 15.Fischer J, Stawarczyk B, Hämmerle CH. Flexural strength of veneering ceramics for zirconia. J Dent. 2008;24:471–5.Google Scholar
- 24.Ban S. Properties of zirconia for realization of all-ceramic restoration. Shikwa Gakuho. 2007;107:670–84.Google Scholar
- 26.Anusavice KJ. Phillip’s Science of Dental Materials. 12th ed St. Louis: Elsevier; 2013. P. 239.Google Scholar