## 3 Results  
The output produced by the model is displayed in Figure 2 and consists of a series of contours, bounding boxes surrounding those contours, and a label indicating the teeth (according to the ISO 3950 classification); the latter is accompanied by a confidence value. The model achieved high detection accuracy on the test set (98.4%) with a Dice index of 0.87. This quality of the performance can also be illustrated by comparing the segmentation with the corresponding ground truth, as shown in Figure 3.  
The teeth-specific distribution of the Dice index and accuracy are displayed in Table 1 for permanent teeth and in Table 2 for deciduous teeth. Figure 3: Example of ground truths (**A**,**B**) and corresponding predictions (**C**,**D**) for two panoramic RX images. Figure 2: Example of output of the Mask-RCNN on a panoramic RX. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**ISO 3950 Code** & **Name** & **Dice Index** & **Accuracy (\%)** \\ \hline
11 & Maximly central incisor (R) & 0.78 & 86.67 \\
12 & Maximly lateral incisor (R) & 0.89 & 100 \\
13 & Maximly canine (R) & 0.88 & 100 \\
14 & Maximly first premolar (R) & 0.85 & 100 \\
15 & Maximly second premolar (R) & 0.85 & 97.61 \\
16 & Maximly first molar (R) & 0.88 & 100 \\
17 & Maximly second molar (R) & 0.88 & 100 \\
18 & Maximly third molar (R) & 0.90 & 100 \\
21 & Maximly central incisor (L) & 0.90 & 100 \\
22 & Maximly lateral incisor (L) & 0.89 & 100 \\
23 & Maximly canine (L) & 0.90 & 100 \\
24 & Maximly first premolar (L) & 0.88 & 100 \\
25 & Maximly second premolar (L) & 0.85 & 95 \\
26 & Maximly first molar (L) & 0.91 & 100 \\
27 & Maximly second molar (L) & 0.85 & 97.61 \\
28 & Maximly third molar (L) & 0.77 & 86.67 \\
31 & Mandibular central incisor (L) & 0.91 & 100 \\
32 & Mandibular lateral incisor (L) & 0.91 & 100 \\
33 & Mandibular canine (L) & 0.88 & 94.59 \\
34 & Mandibular first premolar (L) & 0.88 & 97.5 \\
35 & Mandibular second premolar (L) & 0.86 & 95.45 \\
36 & Mandibular first molar (L) & 0.88 & 97.83 \\
37 & Mandibular second molar (L) & 0.85 & 100 \\
38 & Mandibular third molar (L) & 0.86 & 100 \\
41 & Mandibular central incisor (R) & 0.81 & 97.87 \\
42 & Mandibular lateral incisor (R) & 0.82 & 97.83 \\
43 & Mandibular canine (R) & 0.88 & 97.78 \\
44 & Mandibular first premolar (R) & 0.86 & 97.67 \\
45 & Mandibular second premolar (R) & 0.862 & 95.45 \\
46 & Mandibular first molar (R) & 0.92 & 100 \\
47 & Mandibular second molar (R) & 0.93 & 100 \\
48 & Mandibular third molar (R) & 0.78 & 100 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Dice index and accuracy for the different permanent teeth. \begin{table}
\begin{tabular}{c c c} \hline \hline
**ISO 3950 Code** & **Name** & **Dice Index** & **Accuracy** \\ \hline
51 & Maximly central incisor (R) & 0.90 & 100 \\
52 & Maximly lateral incisor (R) & 0.87 & 100 \\
53 & Maximly canine (R) & 0.72 & 100 \\
54 & Maximly first molar (R) & n/a & n/a \\
55 & Maximly second molar (R) & n/a & n/a \\
61 & Maximly central incisor (L) & n/a & n/a \\
62 & Maximly lateral incisor (L) & 0.85 & 100 \\
63 & Maximly canine (L) & 0.86 & 100 \\
64 & Maximly first molar (L) & 0.87 & 100 \\
65 & Maximly second molar (L) & 0.92 & 100 \\
71 & Mandibular central incisor (L) & 0.87 & 100 \\
72 & Mandibular lateral incisor (L) & 0.84 & 100 \\
73 & Mandibular canine (L) & 0.83 & 100 \\
74 & Mandibular first molar (L) & n/a & n/a \\
75 & Mandibular second molar (L) & n/a & n/a \\
81 & Mandibular central incisor (R) & n/a & n/a \\
82 & Mandibular lateral incisor (R) & 0.89 & 100 \\
83 & Mandibular canine (R) & 0.91 & 100 \\
84 & Mandibular first molar (R) & 0.85 & 100 \\
85 & Mandibular second molar (R) & 0.72 & 83.33 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Dice index and accuracy for the different deciduous teeth. Some cases do not show values (n/a) because of a lack of those teeth in the 50 cases of the test set.