Dental ceramics offer a desirable alternative to metals as a dental restorative material due to its aesthetic qualities, durability, and biocompatibility.However, current manufacture of ceramic crowns in a conventional oven is a lengthy procedure in which a large oven must be heated to a very high temperature to process a dental crown and then slowly cooled to prevent cracking. Dental laboratories overloaded with requests usually take seven or more days to process the permanent dental restoration with a conventional oven while the patient is fitted with a temporary crown. This time consuming process results in loss of work productivity, involves increased risk of morbidity to patients from problems with a temporary crown and occasional problems with improperly fitted permanent crowns. This study presents the feasibility of using microwave oven to sinter dental ceramics. Objectives: To study the feasibility of sintering dental ceramic crowns in microwave oven and evaluate the resulting properties with crowns sintered in conventional furnace. Methods: Sixty zirconia cylinders were sintered to 1100°C, 1300°C, 1350°C, 1400 and 1450°C in conventaional and microwave furnace by varying the dwell times. Fourteen dental copings were layered with glass ceramics and sintered in the microwave and conventional furnace to 800°C. The resulting percentage density, indentation hardness, fracture toughness, microstructures and modulus of rupture were compared. Results: The mechanical properties of samples sintered by microwave with ramp rates in excess of 70°C per minute were comparable to those of the conventionally sintered samples with a slow ramp rate. Indentation hardness (200g) and fracture toughness were found to be 685 ± 24.5 MPa and 2.26 ± 0.8 Mpa(m) respectively. The average microstrusture had less voids and uniform grain distribution. Conclusions: Microwave sintering can permit rapid and reliable processing of complex dental ceramics with better mechanical, microstructural properties and energy savings

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