that constraint inside the womb is associated with decreased expression of Indian hedgehog protein and noggin. These last two are both important factors influencing bone development. Environmental factors
Environmental factors refer for example to maternal smoking and the maternal exposure to amine-containing drugs. Several research groups have found evidence that these environmental factors are responsible for an increase in the risk of craniosynostosis, likely through effects on fibroblast growth factor receptor genes.On the other hand, a recent evaluation of valproic acid (an anti-epilepticum), which has been implicated as a causative agent, has shown no association with craniosynostosis.Certain medication (like amine-containing drugs) can increase the risk of craniosynostosis when taken during pregnancy, these are so-called teratogenic factors. Hormonal factors
Hyperthyroid induced craniosynostosis is a hormone mediated premature closure. It is thought that the bone matures faster due to high levels of thyroid hormone. Genetic factors
In 6 to 11% of the children born with coronal synostosis, more often involving the bilateral cases than unilateral, other members of the family have been reported that were also born with the same condition. This finding is highly suggestive of a genetic cause, which has possibly been found in the fibroblast growth factor receptor 3 (FGFR3) and TWIST genes.Fibroblast growth factor and fibroblast growth factor receptors regulate fetal bone growth and are expressed in cranial sutures during pregnancy. The transcription factor gene TWIST is thought to decrease the function of FGFR, thus also indirectly regulating fetal bone growth. A relation between the mutations in these genes and craniosynostosis is therefore possible. Moloney et al.
The difference is that this time, the deformity mostly shows at the occiput.By Virchows law, restriction of growth will occur at the ipsilateral side of the head; compensatory growth will occur at the contralateral side of the head. This growth pattern exerts an effect at the base of the skull, which is not even when the child is assessed from a point of view standing behind the child, as well as on the cervical spine, which shows a curvature. In addition, from a point of view standing behind the child, a bulging of the mastoid can be seen. Minimal forehead asymmetries are typically seen. Brachycephaly
Brachycephaly, or a short head, is the result of a closure of both the coronal sutures. Following Virchows law, this will result in a childs head with a restriction of growth in the forward direction and in the backward direction: recessed frontal bones and a flattened occiput. Compensatory growth will occur sideways, due to the sagittal suture, and upwards, due to the lambdoid sutures. Oxycephaly
Oxycephaly, also known as turricephaly and high-head syndrome, is a type of cephalic disorder. This is a term  sometimes used to describe the premature closure  of the coronal suture plus any other suture, like the lambdoid suture,

Pansynostosis
The word pansynostosis is also Greek-derived and can be translated as "all one bone", indicating that all of the sutures are closed. In general practice, the term is used to describe the children with three or more cranial sutures closed.Pansynostosis can present in several ways.