ÖZET Aim: The purpose of this laboratory investigation was to evaluate the bond strength of temporary cement [(Provicem, Procem (eugenol-free), Tempbond (eugenol)] to commonly used core build-up materials. [Composite resin (President), Compomer (Dyract AP), glass-ionomer cement (Ionofil), resin modified glassionomer cement (Vitremer) (RMGIC)]. Materials and Methods: Sixty specimens were fabrica...

STATEMENT OF PROBLEM Provisional prostheses are subject to flexure under function. Selection of the appropriate material for their fabrication is difficult given the limited evidence-based information on the flexural strength of provisional resins. PURPOSE This study compared the flexural strength of 5 methacrylate-based resins and 8 bis-acryl resins used to fabricate provisional crowns and f...

STATEMENT OF PROBLEM The in vitro effectiveness of a uniform circumferential ferrule has been established in the literature; however, the effect of a nonuniform circumferential ferrule height on fracture resistance is unknown. PURPOSE This in vitro study investigated the resistance to static loading of endodontically treated teeth with uniform and nonuniform ferrule configurations. MATERIAL...

Background: Metal ceramic restorations are highly popular and are used for most of the crown and bridge restorations made today. Aims: To evaluate the translucency and fracture strength of two all-ceramic and traditional metal ceramic crowns. Materials and Methods: Thirty crowns of similar size and shape were constructed to fit a standard brass die. Ten crowns were manufactured from each of the...

The purpose of this study was to investigate how water aging of the resin cement influences the stress distribution in all-ceramic crowns and if there is an increase in the propensity for crown failure. The failure of all-ceramic crowns attributed to cement degradation was explored using a combination of experimental and numerical methods. Sectioned all-ceramic crown specimens were fabricated o...

OBJECTIVE This study compared the marginal gap, internal fit, fracture strength, and mode of fracture of CAD/CAM provisional crowns with that of direct provisional crowns. MATERIAL AND METHODS An upper right first premolar phantom tooth was prepared for full ceramic crown following tooth preparation guidelines. The materials tested were: VITA CAD-Temp®, Polyetheretherketone "PEEK", Telio CAD-...

PURPOSE The purpose of this study was to investigate the diametral tensile strength of polymer-based temporary crown and fixed partial denture (FPD) materials, and the change of the diametral tensile strength with time. MATERIAL AND METHODS One monomethacrylate-based temporary crown and FPD material (Trim) and three dimethacrylate-based ones (Protemp 3 Garant, Temphase, Luxtemp) were investig...

We quantitatively modeled the volume phase transition of a hydrogel containing a crystalline colloidal array with a crown ether ligand which binds Pb2+. The hydrogel volume response and the wavelength diffracted depend on the Pb2+ concentration and on both the ionic strength and the valence of the nonbinding ionic species. We successfully modeled the response of this hydrogel Pb2+ sensor to ion...

Relationships between tree height and crown dimensions and trunk diameter were determined for shade-tolerant species of old-growth forests of western Oregon. The study included both understory and overstory species, deciduous and evergreen angiosperms and evergreen conifers. A comparison of adult understory species with sapling overstory species of similar height showed greater crown width and ...