This is referred to as the yield stress required to initiate flow.Īlthough plasma is mostly water, it also contains other molecules such as electrolytes, proteins (especially albumin and fibrinogen), and other macromolecules. Because of the high degree of interaction between the elements of blood when it is not flowing, a driving pressure significantly greater than zero is required for stationary blood to start flowing again. This can cause red cells to stick together and form chains of several cells ( rouleau formation) within the microcirculation, which increases the blood viscosity. Unlike water, blood is non-Newtonian because its viscosity increases at low flow velocities (e.g., during circulatory shock). Low flow states permit increased molecular interactions to occur between red cells and between plasma proteins and red cells. There is an inverse relationship between flow and viscosity therefore, the greater the viscosity the smaller the slope of the flow-pressure relationship, meaning that at a given driving pressure flow will be reduced at higher viscosities. Whole blood has a much higher viscosity than water and therefore the slope of the flow-pressure relationship is less steep (see figure). This is shown in the figure as a linear dashed line for the flow-pressure relationship of water. Water behaves as a Newtonian fluid and therefore under non-turbulent conditions, its viscosity is independent of flow velocity (i.e., viscosity does not change with changes in velocity). For example, water is a homogeneous fluid and its viscosity is determined by molecular interactions between water molecules. The interactions between fluid layers depend on the chemical nature of the fluid, and whether it is homogeneous or heterogeneous in composition. This internal friction contributes to the resistance to flow as described by Poiseuille's equation. An all purpose tip for medium viscosity, flowable materials such as composites, core materials and cements.Viscosity is an intrinsic property of fluid related to the internal friction of adjacent fluid layers sliding past one another (see laminar flow). PCR™ Opaque - A grey tip that accommodates a larger volume of material than the clear and black tip. An all purpose tip for medium viscosity, flowable materials such as composites, core materials and cements. Designed to extend the working time of light activated materials. PCR™ Black - A black version of clear tip. PCR™ Clear - The original C-R® syringe tip. The PhotoBloc™ orange color extends the working time of light activated materials. Especially useful for loading luting cements or composites when placing veneers.
Ribbon Tube - A tip with a crimped, flat end for dispensing a thin and wide ribbon of material. Especially useful for injecting materials into postholes and deep proximal boxes.
The PhotoBloc™ orange color extends the working time of light activated materials.ġ9ga NeedleTube - A tip with a 19ga bendable blunt needle, for the most precise placement of slightly thicker materials such as cements, base materials, core buildup materials and any other gel type materials. The PhotoBloc™ orange color extends the working time of light activated materials.Ģ0ga NeedleTube - A tip with a 20ga bendable blunt needle, for the most precise placement of materials such as cements, base materials, core buildup materials and any other gel type materials. Large opening allows placement of even the most heavy bodied materials into small areas. High Viscosity - A tip for high viscosity, heavy materials such as thick composites and core buildup materials. The tip can be clipped to a larger opening if needed. Low Viscosity - An all purpose tip for medium viscosity, flowable materials such as composites, core materials and cements.
Which tubes & plugs are right for my application?ĭepending on the type of material and application there is an AccuDose® tube and plug available. Yes, AccuDose® tubes and plugs can be used with all syringes currently on the market. Call us for more information, 1-20.Ĭan any syringe be used with an AccuDose tube & plug? Yes, additional plugs can be purchased separately. Yes, the PhotoBloc orange AccuDose tubes and plugs can be pre-loaded with light activated material.Ĭan additional plugs be purchased separately? No, tubes and plugs cannot be sterilized.Ĭan tubes & plugs be preloaded with light-activated material?
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