Editing Skull (section)

===Injuries and treatment===
Injuries to the brain can be life-threatening. Normally the skull protects the brain from damage through its high resistance to deformation; the skull is one of the least deformable structures found in nature, needing the force of about 1 ton to reduce its diameter by 1&nbsp;cm.<ref>{{Cite journal|last=Holbourn|first=A. H. S.|date=9 October 1943|title=Mechanics of Head Injuries|journal=[[The Lancet]]|volume=242|issue=6267|pages=438–41|doi=10.1016/S0140-6736(00)87453-X}}</ref> In some cases of [[head injury]], however, there can be raised [[intracranial pressure]] through mechanisms such as a [[subdural haematoma]]. In these cases, the raised intracranial pressure can cause herniation of the brain out of the foramen magnum ("coning") because there is no space for the brain to expand; this can result in significant [[brain damage]] or death unless an urgent operation is performed to relieve the pressure. This is why patients with [[concussion]] must be watched extremely carefully. Repeated concussions can activate the structure of skull bones as the brain's protective covering.<ref>{{cite web|url=https://neurosciencenews.com/concussion-skull-thickening-21352/|title=Repeated Concussions Can Thicken the Skull|date=September 2, 2022}}</ref>

Dating back to [[Neolithic]] times, a skull operation called [[trepanning]] was sometimes performed. This involved drilling a ''burr'' hole in the cranium. Examination of skulls from this period reveals that the patients sometimes survived for many years afterward. It seems likely that trepanning was also performed purely for ritualistic or religious reasons. Nowadays this procedure is still used but is normally called a [[craniectomy]].

In March 2013, for the first time in the U.S., researchers replaced a large percentage of a patient's skull with a precision, [[3D printing|3D-printed]] [[polymer]] [[Implant (medicine)|implant]].<ref>{{cite web|url=https://www.medicaldaily.com/3d-printed-polymer-skull-implant-used-first-time-us-244583|title=3D-Printed Polymer Skull Implant Used For First Time in US|date=7 March 2013|website=Medical Daily|archive-url=https://web.archive.org/web/20130928042619/http://www.medicaldaily.com/3d-printed-polymer-skull-implant-used-first-time-us-244583|archive-date=28 September 2013|url-status=live|access-date=24 September 2013|df=dmy-all}}</ref> About 9 months later, the first complete cranium replacement with a 3D-printed plastic insert was performed on a Dutch woman. She had been suffering from [[hyperostosis]], which increased the thickness of her skull and compressed her brain.<ref>{{cite web|url=https://www.dutchnews.nl/news/2014/03/dutch_hospital_gives_patient_n/|title=Dutch hospital gives patient new plastic skull, made by 3D printer|date=26 March 2014|website=DutchNews.nl|archive-url=https://web.archive.org/web/20140328121216/http://www.dutchnews.nl/news/archives/2014/03/dutch_hospital_gives_patient_n.php|archive-date=28 March 2014|url-status=live|df=dmy-all}}</ref>

A study conducted in 2018 by the researchers of [[Harvard Medical School]] in Boston, funded by [[National Institutes of Health]] (NIH), suggested that instead of travelling via [[blood]], there are "tiny channels" in the skull through which the [[White blood cell|immune cells]] combined with the [[bone marrow]] reach the areas of [[inflammation]] after an injury to the brain tissues.<ref>{{Cite web|url=https://www.medicalnewstoday.com/articles/322901.php|title=Newly discovered skull channels play role in immunity|last=Cohut|first=Maria|date=29 August 2018|work=[[Medical News Today]]|access-date=30 August 2018}}</ref>