Facial width, total face height, short forehead height, long forehead height, upper face height, nasal bridge length, nose height, morphological face height, and lower face height computed from readings of the Akinlolu-Raji image-processing algorithm were analyzed using z-test (P ≤ 0.
05) in 100% of measured parameters: Total face height, long forehead height, upper face height, morphological face height, nose height, and lower face height [Figure 1].
Distances of the facial width (zygion to zygion), total face height (trichion to gnathion), short forehead height (trichion to glabella), long forehead height (trichion to nasion), upper face height (trichion to subnasale), morphological face height (nasion to gnathion), nasal bridge length (nasion to pronasale), nose height (nasion to subnasale), and lower face height (subnasale to gnathion) were computed in this study [Figure 1].
Upper face height
-Mouth width Index (Figure 11, colour plate II) (Sn-St/ChR-ChL, males= 0.
These included thigh length, leg length, upper arm length, forearm length, bi-iliocristal diameter, bitrochanteric diameter, transverse chest diameter, chest depth, biacromial diameter, head length, head breadth, chest circumference, upper arm circumference, calf circumference, biocular breadth, bizygomatic breadth, bigonial breadth, upper face height
, trunk length, and crown-rump length.
A variety of factors have been theorized and reported to be responsible for lower incisor segment such as inclination of mandibular incisors during mixed dentition,4 inclination and size of mandibular permanent 1st molars5, high mandibular plane angles, short mandibular body lengths, great upper face height, and small vertical dimensions in upper posterior segments6.
One of the earliest studies conducted on the relationship between lower arch crowding and vertical craniofacial dimensions was by Sakuda et al6 in 1976 and they found a positive relationship of lower arch crowding with high mandibular plane angles, short mandibular body lengths, great upper face height, and small vertical dimensions in the upper posterior segments.