pattern provides the necessary space for the growing brain, but results in an abnormal head shape and abnormal facial features. in cases in which the compensation does not effectively provide enough space for the growing brain, craniosynostosis results in increased intracranial pressure leading possibly to visual impairment, sleeping impairment, eating difficulties, or an impairment of mental development. a copper beaten skull is a phenomenon wherein intense intracranial pressure disfigures the internal surface of the skull. the name comes from the fact that the inner skull has the appearance of having been beaten with a ball-peen hammer, such as is often used by coppersmiths. the condition is most common in children. injuries and treatment injuries to the brain can be life-threatening. normally the skull protects the brain from damage through its hard unyieldingness; the skull is one of the least deformable structures found in nature with it needing the force of about 1 ton to reduce the diameter of the skull by 1 cm. in some cases, however, of head injury, 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. 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-printed polymer implant. 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. 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 immune cells combined with the bone marrow reach the areas of inflammation after an injury to the brain tissues. transgender procedures surgical alteration of sexually dimorphic skull features may be carried out as a part of facial feminization surgery, a set of reconstructive surgical procedures that can alter male facial features to bring them closer in shape and size to typical female facial features. these procedures can be an important part of the treatment of transgender people for gender dysphoria. society and culture adam was believed to have been buried on mount calvary. silk embroidery (17th century). artificial cranial deformation is a largely historical practice of some cultures. cords and wooden boards would be used to apply pressure to an infant's skull and alter its shape, sometimes quite significantly. this procedure would begin just after birth and would be carried on for several years. osteology like the face, the skull and teeth can also indicate a person's life history and origin. forensic scientists and archaeologists use quantitative and qualitative traits to estimate what the bearer of the skull looked like. when a significant amount of bones are found, such as at spitalfields in the uk and jōmon shell mounds in japan, osteologists can use traits, such as the proportions of length, height and width, to know the relationships of the population of the study with other living or extinct populations. the german physician franz joseph gall in around 1800 formulated the theory of phrenology, which attempted to show that specific features of the skull are associated with certain personality traits or intellectual capabilities of its owner. his theory is now considered to be pseudoscientific. sexual dimorphism in the mid-nineteenth century, anthropologists found it crucial to distinguish between male and female skulls. an anthropologist of the time, james mcgrigor allan, argued that the female brain was similar to that of an animal. this allowed anthropologists to declare that women were in fact more emotional and less rational than men. mcgrigor then concluded that women's brains were more analogous to infants, thus deeming them inferior at the time. to further these claims of female inferiority and silence the feminists of the time, other anthropologists joined in on the studies of the female skull. these cranial measurements are the basis of what is known as craniology. these cranial measurements were also used to draw a connection between women and black people. research has shown that while in early life there is little difference between male and female skulls, in adulthood male skulls tend to be larger and more robust than female skulls, which are lighter and smaller, with a cranial capacity about 10 percent less than that of the male. however, later studies show that women's skulls are slightly thicker and thus men may be more susceptible to head injury than women. however, other studies shows that men's skulls are slightly thicker in certain areas. as well as some studies showing that females are more susceptible to head injury (concussion) than males. men's skulls have also been shown to maintain density with age, which may aid in preventing head injury, while women's skull density slightly decreases with age. male skulls can have more prominent supraorbital ridges, a more prominent glabella, and more prominent temporal lines. female skulls generally have rounder orbits, and narrower jaws. male skulls on average have larger, broader palates, squarer orbits, larger mastoid processes, larger sinuses, and larger occipital condyles than those of females. male mandibles typically have squarer chins and thicker, rougher muscle attachments than female mandibles. craniometry the cephalic index is the ratio of the width of the head, multiplied by 100 and divided by its length (front to back). the index is also used to categorize animals, especially dogs and cats. the width is usually measured just below the parietal eminence, and the length from the glabella to the occipital point. humans may be: dolichocephalic — long-headed mesaticephalic — medium-headed brachycephalic — short-headed the vertical cephalic index refers to the ratio between the height of the head multiplied by 100 and divided by the length of the head. humans may be: chamaecranic — low-skulled orthocranic — medium high-skulled hypsicranic — high-skulled terminology chondrocranium, a primitive cartilaginous skeletal structure endocranium epicranium pericranium, a membrane that lines the outer surface of the cranium history trepanning, a practice in which a hole is created in the skull, has been described as the oldest surgical procedure for which there is archaeological evidence, found in the forms of cave paintings and human remains. at one burial site in france dated to 6500 bce, 40 out of 120 prehistoric skulls found had trepanation holes. additional images an african elephant skull in the cleveland museum of natural history a vulture skull king cobra skull