The Optical Properties of Teeth
Restorative dental materials have physical and optical properties that attempt to mimic the properties of teeth. Many modern monolithic ceramic materials have defined predictable crystalline structures that do not scatter light in the same way as a natural tooth. To compensate for these esthetic properties, the dental technician must layer different colors and opacities of material. Light scattering within homogenous monolithic materials makes the replication of teeth very difficult. The natural tooth section on the right is .55mm thick. From this cross section it is easy to see the optical complexities of tooth structure. The feldspathic ceramic cross section on the left is 1.5mm thick. This cross section shows the different layers of material that are necessary to mimic natural teeth. The sample in the center is a replica of the left sample. It is made from monolithic zirconia. The zirconia cross section shows the optical challenges the dental technician faces when using this material to match teeth. Monolithic materials have gained in popularity, but present many esthetic challenges.