Fig 1.
The mandible of a 17m old pig showing the volume of the mandibular canal.
The volume of mandibular canal (VCM) appears in green and the length of mandibular canal (LCM) as the dashed red line.
Fig 2.
3D rendering of the head of a minipig (A) and a transverse section view at the level of the posterior mental foramen (B).
(A) Arrowed is the prominent posterior mental foramen. Image (B) shows the measured parameters with (a) Maximal vertical depth, (b) Maximal oblique depth, (c) Maximal width of mandibular canal, (d) Alveolar bone height, (e) Inferior bone thickness and (f) Alveolar ridge width. The white arrows indicate the posterior mental foramen.
Table 1.
Mean values and standard deviations of all measured parameters.
Because data from all measure of the left and right hemimandibles were statistically similar, data from the left and right hemimandibles were pooled for this table.
Table 2.
Overview of the correlation between left and right hemimandibles, correlation with age and with body weight.
A correlation coefficient (r) between 0.45 to 0.59 was considered to be a moderate correlation, whereas a correlation coefficient between 0.60 to 0.79 was considered to be a strong and from 0.80 to 1.0 to be a very strong correlation. The significance levels are reported as *p<0.05; **p<0.01; ***p<0.001; ns = p>0.05.
Fig 3.
Dot plots of the measured parameters VCM (A), LCM (B), MVD (C) and MOD (D).
The blue circles are for the left and the red squares for the right hemimandibles. VCM is given in millilitres, all others in millimetres.
Fig 4.
Transverse plane view at the level of the first molar tooth (M1) of two different minipigs.
Where (A) is a minipig with a VCM of 4.88 mm (left) and 4.71 mm (right); (B) is a minipig with VCM of 12.52 mm (left) and 13.41 mm (right). The broken red line in (B) is the nasal septum, the orange areas are the lumina of the mandibular canals and the blue ellipse indicates the position of the inferior alveolar artery that lies beneath the inferior alveolar nerve.
Fig 5.
Dot plots of the measured parameters WCM (A), ABH (B), IBT (C) and ARW (D).
The blue circles are for the left hemimandible and the red squares for the right. All parameters are given in millimetres.
Fig 6.
3D transverse section view and mandibular canal reconstruction.
Where (A) is a transverse image at M2. The loss of spongy bone within the space around the tooth roots white arrows is shown by white stars. The residual spongy bone is demonstrated by a red oval. The green dashed lined indicate the normal superior extent of the mandibular canal. Image (B) shows the segmented mandibular canal where the dashed red line indicates the level of the second molar where image (A) was taken.
Fig 7.
A visual comparison of mandibular canals from animals of two different age groups.
Where (A) is of a 12m old minipig with a canal volume of 2.4 ml and (B) is of a 17m old animal with a canal volume of 9.9 ml. The images are scaled to size.
Fig 8.
Visualization of the changes in mandibular canal volume over time.
The white arrow shows the incisive canal, which is the anterior prolongation of the mandibular canal. The lower image shows the merged segmentations to enable a better visual comparison. The orange segmentation is at 17m and the bright blue at 21m.
Fig 9.
Mandibular canals and inferior alveolar vessels.
Where (A) shows the typical mandibular canal outline (12.5 ml) of a 21-month-old animal. Image (B) shows the same canal but with the inferior alveolar artery (red) having a straight route and the inferior alveolar vein (blue) having an undulating route. In Image C, the inferior alveolar vessels anteriorly have a straight course.
Fig 10.
Medial longitudinal excavation of the mandibular canal of a Göttingen minipigs’ right hemimandible showing the inferior alveolar neurovascular bundle.
The inset shows the inferior alveolar nerve (2) and the inferior alveolar vein (1) and artery (3). The mandibular foramen is indicated by a black ellipse.