Abstract
To examine a relation of angles among the coronal, sagittal and lambdoid sutures to the size of the calvaria as well as to the remains of the metopic suture, 158 adult Japanese calvae or calottes were observed. The calvae used consisted of four groups: group M composed of 74 male calvae without the metopic suture; group F, of 41 female calvae without the same suture; group Un, of 27 sex-unknown calvae without the same suture; and group Um, of 16 sex-unknown calvae with the same sututre. The angles among the sutures were measured at both bregma and lambda. The size of the calvaria was represented by bistephanic arc and breadth (distance between the stephanions), and by parietal sagittal arc and chord (distance from the bregma to the lambda).
Results obtained were as follows. The distances both between the stephanions and from the bregma to the lambda were larger in M than in F, though these distances in M, F and Un were much the same as those in Um. The bistephanic index (breadth/arc) was higher in Um than in F, Whereas the sagittal parietal indices (arc/chrod) in M, F and Um were similar to one another. Apical angle of the frontal squama was larger in M than in F, and was larger in Um than in M and F. However, apical angle of the occipital squama showed no difference among M, F and Um. Finally, a positive correlation was found between the bistephanic distance and the apical angle of the frontal squama only in Um, because the course of the coronal suture was more curved in Um than in M and in F.
Thus it was concluded that in either sex the angles among the sutures at both bregma and lambda are almost constant without distinction of the size of the calva, and that the apical angle of the frontal squama is larger in males than in females, and further that in both sexes the frontal squama between the stephanions becomes swollen and its apical angle increases when the metopic suture remains.
