The effect of different materials and cavity designs on fracture resistance of ceramic partial coverage.

Background: Two intra-coronal preparation designs with varying extensions of cuspal coverage can perform differently regarding their fracture resistance against introral forces.

Methods: Two materials (IPS e-max CAD [EX], VITA ENAMIC [EN]), and two different preparation designs (EX-D1), (EX-D2), (EN-D1), and (EN-D2) were investigated to compare their fracture resistance. A total of 40 (n = 40) caries free human mandibular molars were used.

Fracture Resistance of Different Designs of a Resin-Bonded Fixed Dental Prosthesis: An In Vitro Study.

Purpose: To evaluate the effect of three two-retainer designs of a resin-bonded fixed dental prosthesis (RBFDP) on fracture resistance.

Materials And Methods: A total of 21 three-unit, all-ceramic RBFPDs were fabricated to replace a missing maxillary lateral incisor. The prostheses were divided into three groups of 7 each: Group L (labial RBFPD); Group ML (modified labial RBFPD, fabricated the same as in Group L with additional preparation that included a shallow proximal groove at the pontic side); and Group P, an all-ceramic palatal RBFPD that acted as control.

Association of Micro RNA and Postoperative Cognitive Dysfunction: A Review.

Postoperative Cognitive Dysfunction (POCD) refers to the condition of neurocognitive decline following surgery in a cognitive and sensory manner. There are several risk factors, which may be life-threatening for this condition. Neuropsychological assessment of this condition is very important.

An in vitro assessment of a ceramic-pressed-to-metal system as an alternative to conventional metal ceramic systems.

Purpose: This article reviews a press-on metal (POM) ceramic versus a conventional veneering system regarding marginal gaps, fracture resistance, microhardness, and surface roughness. This was done to provide clinical recommendations for its use.

Materials And Methods: Forty crowns were constructed and divided into two main groups according to the metal coping design.

Influence of veneering materials on the marginal fit and fracture resistance of an alumina core system.

Purpose: This study was undertaken to assess the influence of three-veneering materials on the marginal fit, fracture resistance, and failure pattern of In-Ceram alumina crowns.

Materials And Methods: Forty In-Ceram cores were constructed and divided into four groups of ten each. Ten alumina cores were left unveneered, forming the first group for core testing, while the other 30 copings were divided into three groups depending on the veneering material used.

Bond strength, microhardness, and core/veneer interface quality of an all-ceramic system.

Purpose: This study was designed to evaluate three veneering materials for an all-ceramic alumina system in terms of bond strength, microhardness, and core/veneer interface quality.

Materials And Methods: Fifteen In-Ceram cores were constructed for this study, forming three groups of five specimens each divided by the veneering ceramic disc fired on the occlusal surface of the alumina core: Vitadur N, Vitadur Alpha, or VM7. The specimens underwent shear bond and microhardness testing.

Assessment of an indirect metal ceramic repair system.

Purpose: This study was designed to compare an alternative indirect treatment to repair fractured or chipped veneering metal ceramic using recently developed ultra-low-fusing ceramics.

Materials And Methods: One conventional feldspathic ceramic, Vita Omega, and three ultra-low-fusing ceramics (ULFC), Finesse, Duceram LFC, and Vision-low, were used. Forty ceramic specimens were prepared and divided into two groups.

Effect of light-emitting diode (LED) curing modes on resin/dentin bond strength.

Purpose: This study aimed to compare the effect of three curing modes of a high-powered curing-light source on the shear bond strength and marginal gap of light- and dual-cured adhesive resin cements to dentin.

Materials And Methods: Twelve freshly extracted intact human mandibular molars were selected for this study and stored in the saline solution. Three of the axial surfaces of the teeth were prepared to obtain flat dentinal surfaces.

Effect of artificial saliva storage on microhardness and fracture toughness of a hydrothermal glass-ceramic.

Purpose: This study evaluated the effect of artificial saliva storage on the hardness, crack length, and fracture toughness of a glazed, polished, and bleached hydrothermal low-fusing glass-ceramic (Duceram LFC).

Materials And Methods: Forty ceramic discs were constructed. The discs were assigned to four groups (n = 10) according to their surface finish: Gp1 -- Autoglaze, Gp2 -- Autoglaze/ground/diamond-polished, Gp3 -- Overglaze, Gp4 -- Overglaze/ground/diamond-polished.

Effect of two methods of reinforcement on the fracture strength of interim fixed partial dentures.

Purpose: This study assessed the efficiency of reinforcing provisional restorations by adding a fine gauze metallic mesh or polyethylene fibers between the abutments spanning the pontic length.

Materials And Methods: Forty-five resin fixed partial dentures (FPDs) were constructed using three provisional resins. The three resin groups were further divided into three subgroups depending on their reinforcement.

The effect of a bleaching system on properties related to different ceramic surface textures.

Purpose: This study examined the effect of a manufacturer's proposed bleaching protocol on surface properties of a low-fusing ceramic.

Materials And Methods: Forty ultra low-fusing ceramic samples (Ducera LFC) were constructed for this study. Half the discs were autoglazed, and the other half were overglazed.

Effect of surface treatment on roughness and bond strength of a heat-pressed ceramic.

Statement Of Problem: Bonding ceramic restorations to tooth structure relies on treatment of the ceramic intaglio surface, selection of a suitable resin luting agent, and appropriate treatment of prepared tooth structure. Various ceramic surface treatments have been advocated which produce different topographies and bond strengths, but little information is available to identify the interaction between the resulting surface topography and bond strength.

Purpose: The purpose of this in vitro study was to evaluate the effect of surface treatments on surface roughness and bond strength to dentin and enamel of a commercially available heat-pressed dental ceramic (IPS Empress).

Protective effect of N-acetylcysteine against radiation induced DNA damage and hepatic toxicity in rats.

The present study was designed to evaluate the radioprotective effect of N- acetylcysteine (NAC) on gamma-radiation induced toxicity in hepatic tissue in rat. The cellular changes were estimated using malondialdehyde (MDA, an index of lipid peroxidation), superoxide dismutase (SOD), glutathione peroxidase (GSHPx), reduced glutathione (GSH), and total nitrate/nitrite (NO(x)) as markers of hepatic oxidative stress in rats following gamma-irradiation. The DNA damage was determined by agarose gel electrophoresis.

Silymarin modulates Cisplatin-induced oxidative stress and hepatotoxicity in rats.

Cisplatin (CDDP) is a widely used anticancer drug, but at high dose, it can produce undesirable side effects such as hepatotoxicity. Because silymrin has been used to treat liver disorders, the protective effect of silymarin on CDDP-induced hepatotoxicity was evaluated in rats. Hepatotoxicity was determined by changes in serum alanine aminotransferase [ALT] and aspartate aminotransferase [AST], nitric oxide [NO] levels, albumin and calcium levels, and superoxide dismutase [SOD], glutathione peroxidase [GSHPx] activities, glutathione content, malondialdehyde [MDA] and nitric oxide [NO] levels in liver tissue of rats.