Publications by authors named "Waldemar G de Rijk"

Objective: The purpose of this study was to determine the ability of a methacrylate resin dentin bonding agent to adhere to the dentin surfaces of prepared and conditioned root canals with either 32% phosphoric acid (PA) or 17% ethylenediaminetetraacetic acid (EDTA).

Methods: Prior to the application of the methacrylate resin, the root canals of 54 intact, caries-free, single- rooted, de-crowned, extracted human maxillary incisor and canine teeth were endodontically prepared and conditioned with either 32% PA or 17% EDTA or with distilled water as the unconditioned control. The resin-treated roots were cross-sectioned at three levels and scanning electron microscope (SEM) imaged for circumferential views of the root canals at 60-90× magnification and site-specific views at 250× magnification, and then randomly coded for independent and blind evaluation by four calibrated examiners.

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Purpose: This study measured the bond strength of the self-adhesive resin cements and a bonded resin cement for crowns bonded to extracted teeth with preparations having a total taper greater than 30 degrees. A crown pull-off test was used with direction of pull along the path of insertion. The CAD/CAM system Cerec was used to create crowns with the pull-off loop as an integral part of the crown structure.

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Three-point bending technology has been widely used in the measurement of bone strength. Quantitative trait loci (QTLs) for bone strength have been identified using mouse femurs. In this study, we investigate the use of mouse tibiae in identification of QTLs that regulate bone strength.

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Background: Synthetic vascular conduits used in traumatic or infected fields have a high failure rate leading to catastrophic consequences including amputation and death. Although efforts to coat vascular grafts with antibiotics have had varying results, we developed a novel coating technique for expanded-polytetrafluoroethylene (ePTFE), which has proven to be effective in vitro. Thus, we hypothesized that the coated grafts would resist infection and have decreased neointimal hyperplasia when used in vivo in a large animal model.

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Vascular reconstruction using prosthetic materials in contaminated fields can lead to infection, graft loss, and subsequent amputation. We hypothesized that minocycline and rifampin bound to an ePTFE graft using a unique methacrylate technology would provide for resistance from infection and controlled antibiotic elution. Kirby Bauer susceptibility testing was performed on plates overlaid with Staph aureus (SA) and Staph epidermidis (SE) using 6 mm diameter discs of uncoated graft or antibiotic coated graft (ABX).

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Purpose: To measure the variations in L*a*b* values of a group of 25 guides and to assess whether shade guides are indeed interchangeable.

Materials And Methods: The L*a*b* values of individual shade tabs were measured with a LabScan(tm) XE scanning spectrocolorimeter (SSC) with a special attachment for reproducibly positioning shade tabs. Each shade guide (Vitapan Classical, Vident) contained 16 shade tabs.

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This study reports the tensile bond strength of orthodontic eyelets (RMO, Inc, Denver, Colo) bonded to human extracted teeth with a resin-modified glass ionomer cement (RMGIC) (Fuji Ortho LC, GC America, Alsip, Ill) and various acid etchants (Etch-37 and All-Etch, Bisco, Schaumburg, Ill; Ultra Etch, 3M Unitek, St Paul, Minn) for enamel preparation before bonding. The enamel etch conditions were as follows: 37% phosphoric acid with silica; 37% phosphoric acid, silica-free; 10% phosphoric acid, silica-free; 10% polyacrylic acid; and unetched enamel. Bond strength was measured by pulling in tension on the eyelet with a 0.

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