I click "save" on my computer today and I wonder if that file will be readable 10 years from now, or 20, or 50… Incredibly, and thankfully, a wealth of historical information has been preserved for hundreds of years, written on parchment; a treated animal skin based material. They didn’t worry about hard disk crashes then, but over the years, the wrong environmental conditions can turn a nicely wound parchment scroll into a solid lump of gelatine; forever entombing its secrets within. Perhaps it was just a shopping list, but what if this degradation has caused the loss of some valuable fragment of historical information? There is hope! Much of the ink used contained enough iron to make it detectable on sensitive X-ray equipment.
Digitally extracted text from the XMT scanned parchment scroll
With computed tomography of sufficient resolution and contrast sensitivity (designed by project leader Graham Davis here), we can build up a complete 3-dimensional map of the location of this ink and then use advanced software algorithms to work out how the parchment was rolled or folded. The final step is then to virtually unroll it and reveal (Greek: αποκαλύπτω/apocalypto) the hidden secrets within. It’s not an easy task, which is why we teamed up with experts at Cardiff University, headed by Tim Wess, to tackle the problem.
Of course, if this valuable scroll has already suffered from years of neglect in the wrong environment, the last thing we want to do is cause any more damage. So another vital part of this project, being undertaken at Cardiff, is to investigate the effects of X-ray exposure on parchment. So far, it looks pretty safe and unless the parchment is wet, we have been unable to detect any measureable damage caused by X-rays.
But what has this to do with dentistry? We have a long history in the development of X-ray microtomography, the miniaturised version of medical CT, for dental research, which made us suitable candidates for this project. We have already seen the Apocalypto Project translated into new research topics in dentistry where the high X-ray contrast sensitivity enables us to resolve secondary and tertiary dentine and to observe the release of strontium ions from a glass ionomer cement.
Dr Graham Davis
+44 20 7882 5967 (Phone)
+44 20 7882 7931 (Fax)
Dental Physical Sciences Unit
2nd Fl. Francis Bancroft Building
Queen Mary, University of London
Mile End Road
- Dr Graham Davis - Reader in 3D X-ray Imaging