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| September 2010 | Courtesy of BEGO USA |
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Waiting a little longer is more accurate! Metal frameworks not fitting consistently? From single tooth restorations to complex implant bar cases, one variable that often effects fit but is highly overlooked is "delayed linear expansion" of dental die stone. Most manufactures of dental die stones state their setting expansion figures based on a 2 hour time period (as recommended by the ADA specification 25). However, most Type IV and V die stones continue to expand for up to 120 hours after being poured. A recent study* found that expansion varies significantly among die stones, with 22 - 71 % of the expansion occurring at 2 hours and full expansion after 96-120 hours. BEGO recommends allowing for a longer die stone set time, before wax-up, on more complex cases ensuring a more accurate fit. The diagram (photo below), provided by Professor Marxkors from the University of Munster, shows the expansion and time relationships of various gypsums. * The Journal of Prosthetic Dentistry Volume 88, Issue 1, pages 26-31 Delayed Linear Expansion of Improved Dental Stone, written by R. Heshmati, W Nagy, C. Wirth, V. Dhuru. | ||||
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 Designing a mandibular partial framework
September 21, 201011:00AM EST Get answers to challenging questions technicians face when making lower partials both functional and aesthetic. $49/1 CDT Credit 
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 For more information, call your local dealer or BEGO USA, 1.800.342.2346 | www.begousa.com | |
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