## 3 Results and Discussion
This result demonstrates the scale of possible misunderstanding related to component deformation at the beginning of the analysis and the importance of accurately defining the reference element. As previously mentioned, different orthodontic impressions were made based on a real jaw model. Both were digitized using different measurement methods: a 3D scanner and CT scanner. Each digitized piece was compared with the \"0 model\". A color deviation map is shown in Figure 8 for the silicone material and in Figure 9 for the polyether material. Figure 7: Comparison of jaw models digitized on an optical 3D scanner and micro-CT. In the presented examples, a significant deviation value of more than 1 mm was observed in the maximum case. When comparing deviations between the dental impression model obtained from the 3D scanner and that obtained from the micro-CT, a similar trend was observed, but the deviation values differed in the examined areas by a few tenths of a millimeter. At this stage of analysis, it should be noted that the orthodontic impression materials were characterized by a certain susceptibility to deformation under external influences, which could be observed by introducing dental plaster materials into the impression. The next step in the analysis was to measure the plaster model before removal from the impression. The combined elements were digitized using a micro-CT scanner, as shown in Figure 10. The constructed cross-section in the area of the anterior teeth shows how the boundary between the two elements was formed based on the density of the material. The model created from the separation of the digital impression and the plaster did not feature the defects and damage that can occur during separation. Figure 8: Comparison of scans of the silicone impression obtained on an optical 3D scanner (**a**) and micro-CT (**b**). Figure 9: Comparison of scans of a polyether pulp impression obtained using an optical 3D scanner (**a**) and micro-CT (**b**). Once the plaster models were separated from the impression materials, they were digitized using a 3D scanner and micro-CT. The results were analyzed in the same way as the impressions. Color deviation maps to visualize the deformation of the models in relation to the \"0 model\" are shown in Figures 11 and 12. The results presented show a reasonably uniform match between the plaster model based on the silicone impression matrix and the jaw model on both sides. The third incisal tooth presented a deviation value of \(-0.17\) mm, the highest in the entire dental arch. Here, the poorer fit of the models created via micro-CT is clearly noticeable. Large deviations were noted for the right side of the jaw. Teeth 4, 5, and 6 showed deviations of approximately 0.5 to 1.0 mm at the top. On the other hand, at the base, the deviations ranged from approximately \(-0.5\) mm to 0.8 mm. Based on a comparison, the geometry of the plaster model cast from the polyether impression with the jaw model did not match very accurately. Here, we can see a worse fit on the right compared to the left, as well as on the chewing surfaces in relation to the buccal surfaces and on the molars. Analyzing the obtained color deviation maps, a better fit was observed for the silicone material than the polyether material. In most combinations, the largest deviations were on the last molars. Figure 10: Combined orthodontic impression (blue) and dental plaster (grey) digitized using micro-CT. The fit of the gum mapping was not analyzed, as this fit was affected by the irregular filling of the impression with gypsum material. This phenomenon can be clearly seen when analyzing the plaster models created from the polyether impression (Figure 12). Both the 3D scanner and micro-CT scans showed the greatest deviations for the gingival areas. An important aspect in evaluating the mapping of jaws with impression materials is measurements describing the surface structure on a microscale.