A review of the development, anatomy, and physiology of the human cranial vault suggests that post-adolescent ossification of the suture margins is dictated by interactions between tissues of the cranial capsule and forces deriving from ectocranial, endocranial and diploid sources. A model viewing suture physiology as sensitive to changes in the cranial capsule\u27s environment is tested to identify whether several processes stimulate connective tissue transformation in the suture area. Correlation and factor analysis of the suture-to-suture interactions produced results indicating that when age is controlled, endocranial and ectocranial surfaces independently respond to pressures placed on the anterior and posterior portions of the cranial vault. Post-adolescent suture changes appear to be responses to age change in the structures around the cranial capsule. Modeling the suture in terms of external pressures provides a clearer understanding of how the cranial capsule is affected by age
