Soda-lime glass as a binder in reusable experimental investment for dental castings

Satoshi YAGI, Zutai ZHANG, Yoshiteru AIDA, Yasuhiro HOTTA, Yukimichi TAMAKI, Takashi MIYAZAKI
2011 Dental materials journal  
In this study, different glasses were investigated to improve reusable investments. Borosilicate glass (BSG) powder and soda-lime glass (SLG) powder were prepared by milling broken beakers and microscope slides, respectively, and used in experimental investments (I-BSG, I-SLG) by blending glass powder (10wt%) with cristobalite (90wt%). Some properties and casting fits were evaluated with commercial gypsum-bonded investment as the control. Both BSG and SLG were mainly composed of Si, but SLG had
more » ... a large Ca content. The glass transition temperatures were approximately 800°C (BSG) and 700°C (SLG). Experimental investments with heating showed the significantly (p<0.05) higher expansion than that of the control. The compressive strength of I-SLG was higher than that of I-BSG, and increased with temperature. The MOD inlay obtained from I-SLG had a significantly smaller gap than that from I-BSG, and was comparable to the control. These results suggest SLG could be applied clinically as a reusable dental investment.
doi:10.4012/dmj.2011-040 fatcat:tdey54ngmfc33jt5vscnkfr3zy