The sound of a dental drill alone is enough to give most people goosebumps. Unfortunately, it may also be giving them subsurface cracks in their teeth. Conducted with researchers from the University of Medicine and Dentistry of New Jersey, the Naval Dental School, and the University of Maryland at Baltimore, the study found that removing tooth enamel with a coarse diamond bur produced subsurface cracks as long as 50 micrometers to 110 micrometers. Coarse burs also produced a large number of smaller microcracks that, combined with the longer, vertical cracks, may make drilled teeth more susceptible to fracture. The research found that fine diamond burs made with smaller diamond particles were effective in removing damaged areas caused by the coarser burs.
Dentists routinely use coarse burs to remove tooth decay and prepare a tooth for filling.
To avoid possible problems from subsurface cracking, the researchers concluded that dentists should use a coarse diamond bur only for partial drilling and then finish the job with a finer diamond bur. Service Sector Technology Needs Service sector spending on information technology has paid off handsomely, yielding an estimated return of nearly 200 percent. Yet, the complexity of computer networks, fear of being saddled with obsolete technologies, and other issues breed indecision that causes substantial underinvestment in new technology sectorwide. Commissioned by NIST to help guide its strategic planning, the study reviews a range of economic data and contains case studies of technology trends in the retail banking, home entertainment, and health care industries. For the sector as a whole, information technology accounts for more than 80 percent of technology spending.