Originally Published MDDI November
2004
R&D DIGEST
Imaging Cavities in 3-D![]() |
| Researcher Simon Poland of the Institute of Photonics at the University of Strathclyde shows the 3-D display obtained by taking optical slices of tooth images. |
A new imaging technique may be able to detect cavities before they begin causing
a patient pain. Scientists from Glasgow, UK, have found a method that generates
a three-dimensional image of a tooth that provides more information than traditional
x-rays do.
This technique enables us to see an image of the whole of the tooth by building
up optical slices, says John Girkin, MD, associate director at Glasgows
Institute of Photonics at the University of Strathclyde. Theres
no other way, at the moment, of building a 3-D image of the tooth.
Scientists applied a method that was used in the past to obtain optical sections
of microscopic samples for research. Until now, it had never been directly used
for a medical application. It has not been applied to macroscopic samples
before, and definitely not teeth, says Girkin.
Cavities are a result of enamel breakdown and mineral loss, caused by acid production.
By the time any lesions are seen, its usually too late. The new technique
produces image slices that are put together to form a three-dimensional picture,
allowing scientists to see the tooths structure and any defects, such
as mineral loss. It also enables imaging between two teeth, whereas x-rays dont
provide depth information, says Girkin.
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| John Girkin hopes that the 3-D imaging technology will lead to early detection and better treatment of tooth decay. |
Although there are other techniques that use fluorescence technology to identify
decay, they dont catch it early enough, according to Girkin. Generally,
they are looking at a disease that the dentist will need to drill and fill,
he says. Our aim is to get to the tooth before this is required.
A grid is placed in front of a structured infrared light that is shined on the
tooth, and a camera is placed on the other side, taking sets of three images.
A computer manipulates the images to get rid of the grid lines and create a
3-D view of the tooth.
Its infinitely faster [than an x-ray], says Girkin. The entire
process is in real time and takes about 20 seconds. It is even faster if the
dentist wants to take thicker, less in-depth images.
Girkin hopes the device will be further developed to have the capacity to give
data regarding how much mineral is lost in the tooth and its depth. Now
we are looking to start working with somebody to take this through to a commercial
device, he says. Girkin anticipates developing a low-cost instrument that
will gain an early acceptance from dentists, but is aiming for the European
market first.
Getting medical devices approved in the United States is a nontrivial
process, says Girkin. The idea is to get this worked up and turned
into a product within a European context, and then expand it, once we have reliable
data, to America.
Copyright ©2004 Medical Device & Diagnostic Industry





