If you were using a wax for a wax bite registration, you would not want it to flow at mouth temperature, causing distortion of the wax. However, even at mouth temperature, there is a point at which flow is undesirable. If a wax were capable of flowing at room temperature, it would be very difficult to control. Control of the flow and the melting range, which produce a flowable material, is important in manipulating the wax. As the temperature of the wax increases, the viscosity of the wax decreases until the wax becomes a liquid. A flame source is needed if a flowable state is desired.įlow is the movement of wax as molecules slip over each other. In many cases, the operator does not want the wax to flow but only soften. Controlling the temperature of the wax allows operator control of the viscosity of the wax. Because wax is unstable, the operator must be careful to prevent its distortion. The components with lower melting points will soften first then, as the temperature is increased, more components will soften and the wax will eventually flow. Melting Rangeĭental waxes have a melting range, a range of temperatures at which each component of the wax will start to soften and then flow. The operator must regard these properties when making a wax selection, as well as during manipulation of the wax. Properties that contribute to the melting range, flow, thermal expansion, and excess residue are important considerations for dental wax. Use of the wax will determine properties that are desirable for its application. Each component is added to attain the physical properties desirable for the wax application. They are combined or mixed with synthetic waxes, gums, fats, oils, resins, and coloring agents. ![]() These natural waxes contribute properties to the wax but are rarely used in their pure form. Natural waxes are produced from plants, used in carnauba wax insects, used in beeswax and minerals, used in paraffin wax. Composition and Propertiesĭental waxes are composed of a mixture of components from natural and synthetic sources. The assistant and the hygienist, who is assisting or acting as the operator, will frequently manipulate waxes in taking alginate impressions, pouring the impression, and taking a wax bite registration for articulation of the models. The dental assistant and hygienist typically will not fabricate the actual direct or indirect wax pattern for a dental casting, but they do need an appreciation for the many steps in the procedure known as the lost wax technique (described later in this chapter). ![]() In the laboratory, they may be used to box an impression before pouring a gypsum product, as baseplates for full and partial dentures, to hold components together before articulation, and to provide indirect patterns for casting. Clinically, they may be used to fabricate direct waxings for cast restorations, alterations and adaptations for impression trays, and wax bite registrations. Lost Wax Technique the procedure for fabricating a metal restoration by encasing the wax pattern in stone and then vaporizing the wax under high temperatures to leave an empty impression space once occupied by the wax molten wax is then cast into the space and takes the shape of the patternĭental waxes are used in a wide variety of clinical and laboratory dental procedures. Melting Range a range of melting points of the individual components of waxįlow the movement of wax as it approaches the melting rangeĮxcess Residue a wax film that remains on an object after the wax is removed Wax Pattern a duplicate of the restoration carved in wax Obtain a bite registration using bite registration or utility wax. Describe the usual color, form, and use of inlay, casting, baseplate, boxing, utility, and sticky waxes.ħ. Differentiate between direct and indirect waxings and identify which property of dental waxes is most important in their difference.Ħ. Identify the three classifications of waxes.ĥ. Describe the clinical/laboratory significance of each of the properties.Ĥ. Identify the common components of dental waxes.ģ.
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