NaturaZ is pre-sintered zirconina block for dental CAD/CAM. NatruraZ has a high strength and Transparency, because the particle size is very small and uniform, also it has a high density. The product's durability is excellent and has a longevity in the oral cavity with minimal reduction in strength
DMAX's particles, which are 200~250nm in size, is a base powder to created from superior refining technology to produce. The small and uniform particles are both dense and translucent. Producing a disc with a maximum diameter of 400mm, the 300t press zirconia block maintains stable precise quality. CIP (Cold Isostatic Pressing) machine which create 3 tons of pressing force, is used to create uniform and tight products. Precise temperature control is available to manage heat used to maintain certain block strengths.
On the basis of ISO 6872, strength was tested and the graph below shows trial results. As you can see on the graph, it is clear that the strength of NaturaZ is excellent.
The graph below also shows results from comparing NaturalZ to other Zironia blocks in transparency.
The figure below of SEM confirms the grain size to be 200~300nm .
Average Grain size of NaturaZ after sintering for 2hr at 1,500°C : 200~300nm
Aging test of zirconia block in accordance with ISO 13356. Accelerated ageing test in a 134oC, 2 bars autoclave for 1hr is theoretically the same effect as 3~4 years in vivo.
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ISO 13356
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maximum amount of monoclinic phase after accelerated aging
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< 25%
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residual biaxial flexure strength
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> 500 MPa, and decrease not more than 20 %
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The results depending on the sintering temperature, the monoclinic phases 10.5%, 13.9% respectively, are within 25% of ISO 13356. After aging, an average strength of 9% decreased in intensity within 20%of ISO 13356.
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Sintering
Temperature (°C)
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Observed monoclinic phase fraction (%)
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Before aging
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134°C 5hr
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1450
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0.0
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10.5
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1500
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0.0
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13.9
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Material: ZrO2 (Yttrium oxide-stabilized Zirconia)
FDA/CE: FDA (K091096), CE 0120
Density(g/cm3) : 6.07g/cm3
Coefficient of Thermal Expansion (25 - 500°C) : 11.5 x10-6/K