b. Properties. Sticky wax becomes sticky when melted and has the property of
adhering to the surfaces of various materials. Sticky wax is composed of beeswax,
paraffin, and resins. It is usually supplied as hexagonal sticks of various colors, often
orange or purple. It is brittle at room temperature and assumes a thick, liquid
consistency when heated.
Utility wax is used to provide rim locks and otherwise adapt impression trays for
individual impressions, to build up post-dam areas on impressions, and to form a bead
or border on preliminary and final impressions. Utility wax is pliable enough at room
temperature to use without heating. Utility wax is normally issued in stick form and is
usually red in color. When it is supplied in rope form, it is sometimes called rope wax.
Disclosing wax is used to determine unequal pressure points in a denture that
may cause discomfort to the patient. These points are located by painting the wax on
the tissue side of the denture base and holding the denture in place under pressure in
the mouth. The wax flows away from the points needing relief. Disclosing wax is
sometimes known as pressure indicator paste.
3-10. BOXING WAX
Boxing wax is used to form a box around impressions of the mouth when making
a cast (model). The boxing limits the flow of either plaster of Paris or artificial stone
gypsum material. Boxing wax is usually issued in red strips measuring 1 1/2 inches
wide, 12 inches long, and 1/8 inch thick. Boxing wax is soft and pliable enough at room
temperature to be formed into a desired shape without heating. For further softening, a
strip of wax can be passed through an open flame.
3-11. LOW-FUSING IMPRESSION WAX
Low-fusing impression wax is a wax that is especially compounded so that, when
subjected to controlled pressure, it will flow to some extent in the mouth. Its main
ingredient, spermaceti, is obtained from the head of the sperm whale. Low-fusing
impression wax is often used in relining or rebasing complete and partial dentures.
Because it is easily distorted, impressions must be handled with care. Boxing is not
recommended. Separators are not necessary when pouring the cast.