# Comparison of Manual and Automated Capillary Morphometry Measurements in Oral Mucosa: A Pilot Study
## 3 Results
### Length  
The comparison between the automated and manual methods for measuring capillary length revealed significant differences across all examined sites.  
* In the right buccal mucosa, the automated method yielded a mean length of 344.186 \(\pm\) 93.62 \(\upmu\)m, compared to 241.200 \(\pm\) 51.30 \(\upmu\)m for the manual method, with a mean difference of 102.986 \(\upmu\)m (\(p\) = 0.007).
* In the left buccal mucosa, the automated method recorded a mean length of 330.220 \(\pm\) 64.24 \(\upmu\)m, while the manual method reported 239.900 \(\pm\) 36.40 \(\upmu\)m, with a mean difference of 90.320 \(\upmu\)m (\(p\) = 0.001).
* In the lower labial mucosa, the automated method showed a mean length of 310.951 \(\pm\) 63.78 \(\upmu\)m, compared to 185.300 \(\pm\) 32.78 \(\upmu\)m for the manual method, with a mean difference of 125.651 \(\upmu\)m (\(p\) < 0.0001).
* In the upper labial mucosa, the automated method displayed a mean length of 312.346 \(\pm\) 71.26 \(\upmu\)m, versus 186.700 \(\pm\) 42.61 \(\upmu\)m for the manual method, with a mean difference of 125.646 \(\upmu\)m (\(p\) = 0.000).  
Across all sites, the automated method consistently reported longer capillary lengths compared to the manual method, with mean differences ranging between 90.320 \(\upmu\)m and 125.651 \(\upmu\)m. These differences were statistically significant (\(p\) < 0.05) in all cases, indicating a systematic overestimation by the automated method. The data for both methods followed a normal distribution in all sites, as confirmed by the Shapiro-Wilk test (\(p\) > 0.05), supporting the use of parametric statistical tests.  
Figure 5: Bland–[PERSON] plot of automated and manual density.  
These results suggest that the automated method tends to overestimate capillary length compared to the manual method. This discrepancy could be attributed to differences in how the software identifies and measures capillary structures, potentially including more complex or tortuous segments that the manual method might exclude. Further calibration of the automated method may be necessary to align its measurements more closely with those obtained manually, particularly in clinical settings where precision is critical.  
The mean difference between the methods is 111.15 \(\upmu\)m, with limits of agreement (\(\pm\)1.96 SD) ranging from \(-\)24.91 \(\upmu\)m to 247.21 \(\upmu\)m (Figure 6). The systematic overestimation by the automated method could be due to the intrinsic variability of capillary length, which depends on factors such as the orientation of the capillaries relative to the surface and the inclination of the videocapillarose. This variability can occur even when the examination is performed by an experienced operator, as capillary length measurements may fluctuate throughout a video sequence due to micro-movements and changes in focus.  
Although the majority of data points fall within the limits of agreement, the automated method appears to be more sensitive to detecting elongated or tortuous capillary structures. This highlights the importance of careful calibration and interpretation, particularly when comparing automated and manual measurements in dynamic imaging conditions.