Abstract
There is increasing demand for all‐ceramic crowns to improve esthetics and avoid the intraoral use of metal. There are several ways to fabricate all‐ceramic prostheses. The heat‐press method is easily handled, creates less porosity than the conventional powder slurry method, produces consistent quality, and avoids firing shrinkage. Each of the popular brands of heat‐press ceramics has its own heat‐press furnace. The purposes of this study were to determine whether it was possible to use one heat‐press furnace to make different all‐ceramic prostheses, and to compare the fit and hardness of two commercial heat‐press all‐ceramic systems made using the staining technique. Ceramic ingots were analyzed by X‐ray diffraction analysis before heat press. Finesse® All‐Ceramic and OPC 3G® specimens were both heat‐pressed using a porcelain pressing furnace designed for Finesse®. Mesio‐occluso‐distal inlays were cemented to the metal die with temporary cement. Marginal accuracy was measured using a three‐dimensional coordinate measuring machine. Vickers hardness was measured using a microhardness tester. X‐ray diffraction analysis of the ceramic ingots showed that the main peak position for Finesse® was leucite (KAlSi(2)O(6)) and for OPC 3G® was lithium disilicate (Li(2)Si(2)O(5)). The marginal gap for Finesse® was statistically lower than that for OPC 3G® (62.5 ± 15.5 vs 99.4 ± 11.6 mm; p < 0.05). There was no statistically significant difference in hardness between Finesse® and OPC 3G® (613.8 ± 49.2 vs 660.0 ± 34.0 kgf/mm(2); p > 0.05). The marginal gaps for Finesse® and OPC 3G® were clinically acceptable. Therefore, it is possible to use one heat‐press furnace to cast different all‐ceramic systems.