Abstract:The value, the filtered coffee, tea, and cola had slight staining effects on all 6 groups of denture teeth. (J. Oral Sci. 43, 193-205, 2001)

Use of appropriate resin cement systems with different ceramic/glass-polymer materials might promote the bonding capacity of these systems.

The purpose of this study was to determine the effects of staining solutions on the different shades of a dental composite, and to compare these effects with that of distilled water.Two shades of effect (ET1 and ET2) , two shades of enamel (EL and EM) , and two shades of dentin (DA1 and DA2) were used. Specimens were immersed in three staining solutions (chlorhexidine gluconate, filtered coffee, and orange juice) and distilled water.Color changes were characterized using the CIELAB color space. Since significant interactions occurred, the staining effect of each solution on each shade was determined using one-way ANOVA and the levels of factor in one-way ANOVA were compared using Tukey's method (p<0.05) The staining solutions were found to be more chromogenic than distilled water, and EM and DA2 shades were found to be more color-stable.Based on the color change results in this study, chlorhexidine gluconate (1 .45) , filtered coffee (1.43) , and orange juice (1.02) were determined as having "slight" staining effects on the tested shades. As for the tested shades in this study, they revealed acceptable color change results.

Flexural strength of newly developed restorative CAD/CAM materials was significantly decreased by artificial aging. Cyclic loading or HCl exposure does not affect to the flexural strength and structural reliability of Cerasmart™ and Lava™ Ultimate.

It may be concluded that the glazed specimens showed a better color stability, although the staining observed in the polished specimens was not clinically noticeable.

No abstract

The fit between tooth-colored endodontic posts and post spaces should be as tight as possible.

Abstract:The aim of the present study is to evaluate the transverse strength, modulus of elasticity, surface roughness, hardness, and water sorption/solubility of nanoparticle zirconium oxide (nano-ZrO 2 ) added to heat-cured poly(methyl methacrylate) (PMMA) after thermocycling. The specimens were divided into four groups according to the ratio of nano-ZrO 2 addition to heat-cured PMMA; group 1: 5% nano-ZrO 2 ; group 2: 10% nano-ZrO 2 ; group 3: 20% nano-ZrO 2 , and group 4 (control): PMMA without nano-ZrO 2 . A statistically significant decrease in transverse strength was observed by all additional rates of nanoZrO 2 compared with group 4 (control; P < 0.025). When hardness results were evaluated, groups 1 and 2 showed statistically higher values compared with groups 3 and 4 (P < 0.025). The surface roughness of group 3 was statistically higher than the other groups (P < 0.025), but it was within the clinically acceptable limits. As the nano-ZrO 2 addition rate increased, water sorption/solubility values of the specimens also increased. Although nano-ZrO 2 addition had an adverse effect on some mechanical and physical properties of heat-cured PMMA, it increased hardness values, implying that the addition of nano-ZrO 2 would contribute positively to some mechanical properties of PMMA denture base material when nano-ZrO 2 was homogeneously distributed in PMMA.