Fracture statistics of dental ceramics: Discrimination of strength distributions

Abstract

The Weibull distribution is the most widely used function in the reliability analysis and structural design of dental ceramics; however, it is still unclear whether Weibull distribution is always the most suitable one. With wide applications of dental ceramics, a special attention has been paid in discriminating their strength distributions. In this paper, three versatile functions, involving normal, log-normal and Weibull distributions, are applied to the analysis of ten strength data sets of dental ceramics with different compositions and the results are compared in terms of the Akaike information criterion and the Anderson-Darling test. It reveals that various microstructures and compositions in the investigated dental ceramics cause their strength distributions deviated from the Weibull distribution. The influence of microstructure induced fracture properties (multiple-modal flaw size distribution, R-curve behavior and subcritical crack growth) on strength distributions is discussed.

The influence of microstructure on the fracture statistics of polycrystalline diamond and polycrystalline cubic boron nitride

“…They found that for ZnO, the strength data was best characterized by the normal rather than the Weibull distribution. Similar results have also been reported by Basu et al [7] and Nohut and Lu [8] for a variety of advanced and dental ceramics. Nohut [9], looked into the influence sample size has on the choice of an accurate strength distribution.…”

Fracture Strength: Stress Concentration, Extreme Value Statistics, and the Fate of the Weibull Distribution

“…These observations demand a general theoretical explanation. The suggested explanations for these empirical observations include bimodal or multimodal flaw-size distribution [1,[13][14][15], R-curve behavior [6], small size of the data sets [1,9], and thermal-activated crack nucleation [16,17]. Here we provide a general explanation for these observations by showing that the Weibull distribution is unstable in the renormalization-group sense for quasibrittle materials and, thus, not applicable at long length scales.…”

“…The applicability of the Weibull distribution to describe the fracture strength of brittle and quasibrittle materials has been a topic of intense debate [1][2][3][4][5][6][7][8][9]. Several experimental studies argue that the Weibull distribution is not always the best statistical distribution to fit fracture data [1,2,6,8,[10][11][12] (numerous others argue otherwise), particularly for quasibrittle materials that have significant precursor damage.…”

“…Several experimental studies argue that the Weibull distribution is not always the best statistical distribution to fit fracture data [1,2,6,8,[10][11][12] (numerous others argue otherwise), particularly for quasibrittle materials that have significant precursor damage. These observations demand a general theoretical explanation.…”

Strength degradation and lifetime prediction of dental zirconia ceramics under cyclic normal loading

“…Weibull distribution analysis is often used to describe the fracture probability of material, and research strength degradation from the point of statistics [32]. Weibull analytic function can be expressed as [16,33]:…”