MicroCT of a Molar Tooth
“There comes a point in some of our lives where one (or more) of our pearly whites falls victim to the dreaded drill courtesy of a visit to the dentist. Whether it is a tooth which simply outstayed its welcome or a tooth which needed significant reinforcements in the form of fillings, our teeth are an invaluable asset which play an integral part of our daily quality of life. But have you ever wondered what in inside of our powerful incisors, canines, and molars/pre-molars? A member of our wonderful Micro Photonics Inc staff has kindly donated his recently extracted 3rd Molar (L17) for the sake of science!
Performing a microCT scan of a tooth, especially a molar, reveals that the tooth has a very high physical density. High energy x-rays in combination with a metal filter are necessary in order to obtain good quality projection images. Image reconstruction of the tooth reveals the three of four primary layers of a tooth:
Enamel: the hardest and most mineralized part of the tooth (shown in White)
Dentin: A softer-than-enamel material comprised of both inorganic elements and water, it separated the enamel and cementum and supports the crown of the tooth (Shown in Teal)
Pulp: Contains the soft tissue including the blood vessels and nerves of the tooth and is located in the center (Shown in Red)
Cementum: A semi-mineralized substance which covers the root of a tooth. This is not differentiable from dentin in an x-ray microCT image.
A myriad of applications exist for the microCT of teeth including dental tissue engineering, finite element modeling, quantifying enamel thicknesses as a result of drug therapies, fracture risk analysis, and reinforced polymer implant evaluation. Swain et al (2009) have summarized a common list of evaluations in dental research for which microCT allows.