Dynamic fatigue behavior of dental porcelain modified by surface deposition of a YSZ thin film.


Journal Article

PURPOSE: The objective of this study was to evaluate the basic fatigue parameters of a dental porcelain modified by deposition of a yttria-stabilized zirconia (YSZ) thin film and to compare the data to that of an unmodified control. METHODS: Two hundred bars (2 x 2 x 15 mm(3)) were cut from ProCAD blocks. Specimens were wet-polished with 1200-grit SiC abrasive. One surface of each bar was sandblasted with 50 microm Al2O3 abrasive (50 psi). Half the specimens were further modified through deposition of a 3-microm YSZ thin film on the sandblasted surface. Depositions were performed using an radio frequency magnetron sputter system (working pressure of 15 mT, 150 degrees C, 30:1 Ar:O2 gas ratio). Specimens were tested at different stressing rates: 5.0, 0.1, and 0.01 MPa/s (n = 25/group) in deionized water (37 degrees C), and inert strength was determined in air (25 degrees C, 70 MPa/s). All strength measurements were carried out by three-point bending (span = 10 mm) in a servo-electric test system. RESULTS: The mean flexural strength values (MPa) and standard deviation for the uncoated sandblasted group were: 98.6 (5.5), 90.7 (5.9), and 84.2 (8.5), and for the sandblasted + YSZ thin film group: 125 (9.4), 119.3 (7.8), and 102.8 (7.0), for the highest to the lowest stressing rates, respectively. The fatigue parameters n and lnB were calculated by linear regression of dynamic fatigue data. For the uncoated group, n = 38 and lnB = 4.7 MPa(2)/s, and for the coated group, n = 33 and lnB = 10.8 MPa(2)/s. Weibull analysis was also performed showing that the characteristic parameter (sigma(o)) was 113.3 and 125.7 MPa for the uncoated and coated group, respectively. CONCLUSIONS: There was an increase in strength for specimens modified by application of a YSZ thin film. It is hypothesized that thin-film application modifies flaws or residual surface stress states.

Full Text

Duke Authors

Cited Authors

  • Teixeira, EC; Piascik, JR; Stoner, BR; Thompson, JY

Published Date

  • October 2008

Published In

Volume / Issue

  • 17 / 7

Start / End Page

  • 527 - 531

PubMed ID

  • 18761578

Pubmed Central ID

  • 18761578

Electronic International Standard Serial Number (EISSN)

  • 1532-849X

International Standard Serial Number (ISSN)

  • 1059-941X

Digital Object Identifier (DOI)

  • 10.1111/j.1532-849x.2008.00340.x


  • eng