Relative growth of the human fetal skull in width, length and height.
Linear measurements of the width, length and height of the face and cranium were made on 60 fetuses of 49-212 mm crown-rump length. Absolute growth rate was derived from the slope of the regression line of dimensional length against time. There was a high correlation between absolute growth rate and mean dimensional length (r = 0.995; p less than 0.001). The relative growth rate was calculated by dividing the absolute growth rate by the mean dimensional length. Change in shape was measured by the relative increase or decrease in dimensional length once the outlines were normalized to an equal area to eliminate the effect of size. Change of shape correlated highly with relative growth rate (r = 0.95; p less than 0.001). Relative growth rates provide a reliable indication of change in shape, unlike absolute growth rates, which are mainly influenced by size. Measurement of relative growth rates showed an increase in cranial length greater than height greater than width and facial length greater than width greater than height.
Trenouth
M J
MJ
University Dental Hospital, Manchester, U.K.
D000365:Age Determination by Skeleton; D002508:Cephalometry; D002574:Cervical Vertebrae; D005314:Embryonic and Fetal Development; D005145:Face / Q000196:embryology; D005865:Gestational Age; D006801:Humans; D012886:Skull / Q000196:embryology*; D014716:Vertical Dimension