Figure 3. Changes in the size of the craniofacial skeleton and the incremental changes for every 2 wks. Upper lines and left-side scales indicate the cumulative growth in the size of the craniofacial skeleton of rats twice weekly from 5 to 20 wks (n = 7). Lower lines and right-side scales indicate their growth velocity. Significant difference by Student’s t test is indicated by one asterisk (p < 0.05) or two asterisks (p < 0.01). (A) Size of anterior cranial base (S-E). (B) Size of posterior cranial base (S-Ba). (C) Total skull length (Po-A). (D) Nasal bone length (N-A). (E) Viscerocranial height at the first molar (U1-U1'). (F) Maxillary bone length (Mu-Bu). (G) Mandibular corpus length (Go-Pg). (H) Ramus height (Co-Co'). (I) Mandibular effective length (Co-Pg).