Table 4.
Measurements of the cranial base in sagittal sections of human embryos during the late embryonic period.
| CS | 19 | 20 | 21 | 22 | 23 | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| Number of samples | Present study (n = 11) | Diewert (n = 10) | Present study (n = 9) | Diewert (n = 9) | Present study (n = 7) | Diewert (n = 7) | Present study (n = 5) | Diewert (n = 7) | Present study (n = 5) | Diewert (n = 4) |
| (A) | ||||||||||
| Mean CRL (mm) | 16.34 | 18.1 | 17.81 | 21.2 | 20.00 | 22.8 | 21.54 | 25.5 | 26.45 | 29.3 |
| Na-S Distance (mm) | 2.44 ± 0.25 | 2.3 ± 0.4 | 2.71 ± 0.11 | 2.6 ± 0.3 | 2.93 ± 0.19 | 3.4 ± 0.4 | 3.27 ± 0.92 | 3.6 ± 0.3 | 4.04 ± 0.60 | 4.5 ± 0.6 |
| S-Ba Distance (mm) | 2.33 ± 0.18 | 2.5 ± 0.4 | 2.65 ± 0.06 | 2.6 ± 0.5 | 2.82 ± 0.22 | 3.2 ± 0.3 | 3.05 ± 0.26 | 3.3 ± 0.3 | 3.60 ± 0.31 | 3.6 ± 0.3 |
| Na-S-Ba Angle (°) | 127.4 ± 5.62 | 117 ± 4 | 126.6 ± 6.34 | 126 ± 4 | 132.8 ± 4.67 | 127 ± 2 | 127.9 ± 5.51 | 127 ± 5 | 123.6 ± 3.36 | 125 ± 4 |
| Present study | Diewert’s study | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| (B) | ||||||||||
| Na-S Distance (mm) | P < 0.05 | P < 0.001 | ||||||||
| S-Ba Distance (mm) | P < 0.05 | P < 0.001 | ||||||||
| Na-S-Ba Angle (°) | NS ( P = 0.317) | NS | ||||||||
(A) Mean ± standard deviation (SD) for Diewert’s and our studies are presented in this table. Each value of Diewert’s study was obtained by dividing the original value by 36 (see Materials and methods). (B) Significant differences between stages were calculated using the F-test of the analysis of variance. A P-value greater than 0.05 was defined as nonsignificant (NS).
CS Carnegie stage, CRL crown-rump length, Na nasion, S sella, Ba basion.