Material and methods: The marginal and internal fit of 45 zirconia copings was evaluated by a replica technique using a light-bodied silicone. The polymerized silicones were retrieved from the coping and sectioned first in the bucco-palatal dimension and mesio-distal dimension resulting in 14 measurements per coping. The thickness of the polymerized silicone was measured with a traveling light microscope at ×30 magnification.
The differences in the means of the overall, marginal, internal fit and occlusal fit across the main groups was performed using 1-way ANOVA, using SPSS 11.5. and multiple comparisons using post-hoc Tukey's test (α=.05). There was no significant difference in the marginal fit. Procera was significantly different from lava and Renishaw in the internal fit.
Results: The means and standard deviations of the marginal fit were: AllZirkon 61.2 ± 19.3µm, Lava, 55.1 ± 16.5µm, and Incise 47.3 ± 12.4µm. The internal fit for the systems was: 128.8 ± 20µm, 93.4 ± 13.5µm, and 85.3 ± 6.7µm, respectively.
Conclusions: The marginal and overall fit of the 3 systems are within clinically acceptable