One of the most common but often overlooked problems resulting from skull trauma is the cranial suture injury. Cranial suture injuries occur when the skull is thrown against an immovable object ...

[3] Figure 1 illustrates the boney anatomy of the normal skull sutures and fontanelles. The newborn infant's skull is incompletely ossified and the cranial sutures are normally open at birth ...

Look for the sagittal suture – the squiggly line that runs the length of the skull – and note whether is it's completely fused. If it is, the remains are likely to be of someone older than 35.