Temperature Related Physical Changes of Different Materials for Fabrication of Patterns for Casting from Dental Alloys

Introduction: In contemporary dentistry there are a variety of materials which are used for fabrication of patterns that are invested and used as a pattern of the final restoration. Despite the ceaseless introduction of new materials, there is still less information about their physical changes during the process of thermal elimination. Materials and Methods: Four identical samples are prepared from the materials as follows: Pattern resin LC® (GC™), C-cast® (KaVo™ Dental), CAD/CAM wax (Yeti Dental™) and Castable Resin® FLCABL02 (Formlabs™). The samples are heated in furnace staring from 25℃ to 1050℃ and their main temperature related physical and volumetric changes are examined at every rise of temperature by 50℃. Results: When the CAD/CAM wax is heated, it starts melting before any visible volumetric changes of the sample are presented. The rest of the examined materials, as predominantly resin-based materials, start expanding at a specific temperature and after a further temperature rising, they start melting and burning afterwards or just burning rapidly. Conclusion: The main protocols of investing and casting should be modified in accordance to the thermal related physical and volumetric characteristics of the materials used for pattern fabrication.