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DH 104 Vocab
Vocab matching
Question | Answer |
---|---|
Abfraction | wedge-or v-shaped cervical lesion created by the stresses of lateral or eccentric tooth movements during occlusal function, bruxing, or parafunctional activity resulting in enamel microfractures. |
Thermal conductivity | Rate of heat flow through a material. Pulpal sensitivity is likely if conductive materials such as metals are placed in close proximity to the pulp. |
Coefficient of thermal expansion | A measure of the change in volume of a material in relation to the change in temperature. |
Percolation | The process of heating and cooling, and the accompanying opening and closing of the gap. |
Solubility | Amount of material that dissolves in a liquid such as water. |
Sorption | Adsorption and absorption together in a continuing process |
Adhesion | The joining together of two objects using glue or cement. In dentistry, it is used to keep restorations in place. |
Wetting | The ability of a liquid to maintain contact with a solid surface, resulting from intermolecular interactions when the two are brought together. |
Surface tension | Molecules at surface don't have other like molecules on all sides of them & cohere more strongly to those directly assoc'd with them on surface forming a surface "film" making it more difficult to move object through surface than to move when submersed. |
Chroma | The strength or color saturation of the hue, as in pink versus red. |
Corrosion | A process in which a metal is changed to a metal oxide. In dentistry, metal restorations have the potential to do this and so do instruments. |
Tarnish | A chemical or electrochemical attack on a metal surface. Many times corrosion starts as this surface discoloration. |
Tensile Strength | The maximum stretching force that a material such as wire can withstand before breaking. |
Compressive Strength | the maximum compressive stress that under gradually applied load a given solid material will sustain without fracture. |
Shear Strenth | the degree to which a material or bond is able to resist a force acting parallel to the plane. |
Stress | The force that develops in a loaded object. |
Elastic modulus | The slope of a graph of stress versus strain. |
Creep | The small change in shape that results when an object is under continuous compression. |
Hydrodynamic Theory (Dentin tubules) | Mechanism of pain impulse transmission to the pulp as a result of fluid movement within the dentin tubule, which stimulates the nerve endings at the dentinopulpal interface. |
Study Model | A replica of the hard and/or soft oral tissues used primarily for observation of initial baseline data. |
Cast | A working model replica of the hard and/or soft oral tissues on which you can fabricate an appliance or a restoration. |
Die | A working replica of a single tooth or several teeth used to fabricate crowns, inlays, etc. |
Hydrocolloids | impression materials whose major component is water. |
Agar | A reversible hydrocolloid. Used in impressions when the area cannot easily be kept dry |
Sol (state) | A solution of one material dissolved in another |
Gel (state) | occurs in two phases-The first phase is a solid carbohydrate polymer network, like the soap used to create foam. The second phase is water trapped in very small pockets of the material, like the air trapped in the foam formed by the soap. |
Syneresis | Gels contract on standing, squeezing out liquid. This is the process of exudating liquids into the surface of a gel. This occurs with hydrocolloid materials. |
Imbibition | The absorption of fluid by a solid or gel causing it to swell and distort such as occurs with hydrocolloids. |
Microleakage | The seeping and leaking of fluids and bacteria between the tooth/restoration junction or interface. |
Galvanism | Caused when two dissimilar metals are placed together, which is why it is important to place a gold crown next to an amalgam restoration. |
Ductility | A solid material's ability to deform under tensile stress. |
Malleability | A material's ability to deform under compressive stress. |
Metamerism | Different perceptions of color because of various light sources. This can complicate selection of the appropriate shade of restorative material. |