to evaluate the influence of core thickness and fabrication stages on the marginal accuracy of ips e.max press crowns.twenty ips e.max press crowns, 1.5mm thick, were fabricated on metal dies. the crowns had two different core thicknesses, 0.8mm for group a and 1mm for group b, ten for each group. marginal gap was measured after each stage of core fabrication, veneering and glaze firing. the sp...

purpose: the aim of this study was to evaluate the effect of two gingival finishing lines (90° shoulder and deep chamfer) on the marginal fitness of two types of full anatomic all-ceramic crowns; zirconia crowns (zikonzhan) and glass ceramic crowns (ips e-max cad) milled with cad/cam system. materials and methods: two dentoform teeth of left maxillary first molar were prepared with chamfer fini...

The phenomenon of marginal underdominance at a stable equilibrium in a two-locus-two-allele deterministic selection model is studied analytically using bifurcation theory. This technique and additional numerical studies indicate several new aspects of the phenomenon that are of biological importance. Marginal underdominance can occur at both loci simultaneously and can be present in a model wit...

We use individual-based stochastic simulations and analytical deterministic predictions to investigate the interaction between drift, natural selection and gene flow on the patterns of local adaptation across a fragmented species' range under clinally varying selection. Migration between populations follows a stepping-stone pattern and density decreases from the centre to the periphery of the r...

statement of problem: targis restorations provide good esthetic and clinical success; however, improving marginal accuracy requires further investigations. purpose: the aim of this was to study evaluate the effect of relining on the marginal accuracy of ceromer crowns. material and methods: one ivorine maxillary central incisor was prepared for targis crown. 10 acrylic models were duplicated fr...

Previously, personalized service was provided by traditional channel. Now, they are available online by using web channel. Some unique features of a web channel make it different from a traditional channel. Previous research has studied the competition between a web channel and a traditional channel from various angles. In this paper, we develop a model to examine the impact of switching costs ...

background and aim: metal ceramic restorations are widely used in crowns. the marginal fitness of these artificial crowns is prone to alteration during the firing cycle of porcelain. gold electroformed metal-ceramic restorations have been introduced as alternatives to conventional metal-ceramic restorations. however little is known about the relationship between procelain firing procedures and ...