PATTERN WAXES AND INACCURACIES IN FIXED AND REMOVABLE PARTIAL DENTURECASTINGS

It is the desire of every dentist and dental technician to produce a r estoration that will fit the patient with a minimum of adjustments and certainly one that does not require remaking. Yet many abuse the mate rials with which they work, either through improper manipulation, lack of familiarity with their properties, or by attempting to reduce labo ratory time by taking short cuts. Wax is one of the materials that req uires more knowledge and skill to manipulate accurately because it has a considerably higher coefficient of thermal expansion (and contracti on) than any other dental material. It often contributes considerably to the inaccuracies of cast dental restorations. This article provides a review of dental waxes used to make prosthodontic castings and poin ts out some of the properties of waxes that must be controlled to make accurate restorations.