# Left-Right Multimodal Morphometric Comparison of Human Submandibular Glands
## 3 Results  
Linear Morphometry [17]  
The first item was the caliber of the submandibular duct, measured at three distinct portions--proximal, middle and distal third, with the mean totals (\(\pm\)SD) being 1.81 \(\pm\) 0.63 mm, 1.85 \(\pm\) 0.54 mm and 1.74 \(\pm\) 071 mm for the right gland and 1.65 \(\pm\) 0.52 mm, 1.78 \(\pm\) 0.61 mm and 1.80 \(\pm\) 0.51 mm for the left gland, respectively. When comparing the left and the right calibers at the three mentioned sites, there were no statistically significant differences: \(p\) = 0.46, \(p\) = 0.59 and \(p\) = 0.19, respectively. The same result was obtained on evaluating the left-right asymmetry of [PERSON]'s duct length (\(p\) = 0.13). The genu of the submandibular duct was measured in the axial plane; the average on the right was 121.3 \(\pm\) 25.9 degrees, 107.5 \(\pm\) 25.0 degrees, without mutual differences (\(p\) = 0.89). The approximate gland size was measured in the coronal plane, through a maximal longitudinal (mean: right, 44.6 \(\pm\) 12.8 mm; left, 43.7 \(\pm\) 10.1 mm) and maximal transverse (mean: right, 27.0 \(\pm\) 8.0 mm; left, 24.9 \(\pm\) 6.2 mm) diameter of the contours of the gland. Again, there were no left-right differences; the \(p\) values were 0.33 and 0.29 for the longitudinal and transverse diameters, respectively.  
Planimetry of sialograms [18]  
The mean planimetric sizes of the glands were 872 \(\pm\) 154 mm\({}^{2}\) (right) and 836 \(\pm\) 144 mm\({}^{2}\) (left). The first issue was to test the influence of age on the gland size, where a multivariate analysis of variance produced no significance (\(p\) = 0.197). The next step was to compare right and left glands and, again, there was no statistically significant difference (\(p\) = 0.390). When testing the sex differences, the submandibular glands, taken together left and right, were larger in males than in females (\(p\) < 0.001).  
Fractal properties [19]  
The first item analyzed was the length of [PERSON]'s duct, defined intraglandularly as the largest canal extending from the pole of the gland to the extragalundular portion of the duct. The average total duct lengths were 63.8 \(\pm\) 10.2 mm and 61.8 \(\pm\) 8.9 mm for the right and left glands, respectively. The intraglandular portion of the submandibular duct was less than a half of the whole total length (29.4 \(\pm\) 5.4 mm--right, 28.5 \(\pm\) 5.8 mm--left). A paired correlation test found no left-right differences, for both items: the total and intraglandular length, \(p\) < 0.001 and \(p\) = 0.05, respectively. When assessing the course of [PERSON]'s duct, we noted kinks and tortuosities apart from the regular genu of the duct. They were found in 32.4% of the right glands, and 23.7% of the left glands. These values, tested using [PERSON]'s exact test, also correlated statistically (\(p\) = 0.279).  
The next object of interest was, logically, the caliber of the submandibular duct. This dimension is difficult to assess, as it changes along the course of the duct [20]. Therefore, we chose the maximal value of the duct as a more comparable reference for each gland. The mean calibers were 2.6 \(\pm\) 0.5 mm and 2.3 \(\pm\) 0.5 mm for the right and the left glands, respectively. This morphometric factor presented a highly significant correlation (\(p\) < 0.001) between the two glands in each subject.  
The median total number of intraglandular side branches, i.e., affluents to [PERSON]'s duct was nine (SD = 2.5), both for the right and the left glands. Despite the high variability, this number presented a normal distribution, and again, the correlation between the two sides was highly significant (\(p\) = 0.001).  
The last item analyzed was the existence of accessory submandibular lobes/duct. They were found in 8.1% on the right side only, 5.3% on the left side only and in 5.3% bilaterally.