Thermal expansion of prepared dental base-metal casting alloys


Background: This study aimed to evaluate the linear thermal expansion of prepared Ni-Cr and Co-Cr dental basemetalcasting alloys which has been prepared locally in Iraq and compare with other conventional alloys.Materials and methods: Cylindrical shape wax specimen was prepared of (15mm) length and (5mm) diameter,which invested in phosphate-bonded investment material and casted by using induction-casting machine. The linerthermal expansion has been tested by using Iraqi-made dialometer in which the furnace was set to reach from roomtemperature to 950 C in a rate of 10 C per minute.Results and discussion: The prepared Ni-Cr and Co-Cr alloys were showed a higher linear thermal expansion than theconventional alloys, however, statistical analysis revealed non-significant differences regarding the Co-Cr alloys andhighly significant differences regarding the Ni-Cr alloys