The Diagnodent is among one of the newest technologies in locating decay.  It is a small pen shaped laser instrument which scans your teeth with a harmless laser light searching for hidden decay before it destroys tooth structure from the inside out.  Diagnosing cavities beneath the hard surfaces is more challenging because the disease process can start through microscopic defects in the hard surface enamel and can rapidly spread into the softer structure beneath the surface.  X-rays are limited in detecting sub surface decay, especially when the cavity is in its early stages.  The diagnodent allows the dentist to monitor the areas below the hard surfaces and catch decay early. The pen shaped instrument provides instant feedback on the health of the tooth.  It simply glides along the tooth surfaces.  A number scale and an alarm will signal the dentist when there are signs of hidden decay.  This new technology is patient friendly, especially for children.  It is completely safe, pain free and early detection of decay will minimize the expenses related to major tooth repair.