ABSTRACT
Objective: To study the thermal expansion compatibili ty of a newly developed low temperature compensatory die stone (CDS) with Al 2O 3 base coping and to determine its setting time and setting expansion rate. Methods: Using HDS (Hieraus Die Stone ) as control. The ther mal expansion compatibility of CDS with Al 2O 3 was determined with TMA method on Du point 2100 thermometer;the setting time and setting expansion rate of CDS were measured with routine technique. Results: CDS showed much smaller thermal expansion with Al 2O 3 base coping than HDS.When the wa ter/powder ratio increased from 0.20 to 0.30,the setting time (h) of CDS increas ed from 12.75?0.7546 to 19.85?0.7472,that of HDS from 12.25?0.7169 to 24.00? 0.8165. The setting expansion of CDS was similar to that of HDS at various water /powder ratio. Conclusion: CDS has suitable thermal expans ion compatibility with Al 2O 3, it also has proper setting time and setting ex pansion rate to meet the clinical needs.