Effect of polymorphism of SiO2 addition on mechanical properties of Feldspathic porcelains.

The present study aimed to investigate the effects of SiO2 polymorphism on the mechanical properties of feldspathic porcelains. Seven kinds of experimental feldspathic porcelains were prepared using chemical reagents; three types of low-fusing feldspathic glasses and four types of two-phase porcelains by adding 10 or 20 mass% of fused silica (T-F) or cristobalite (T-C). Flexural strength and fracture toughness of these porcelains were evaluated.

[Dental students' smoking behavior and their attitude towards smoking].

This study investigated dental students' smoking behavior and their attitudes, in order to provide programs to patients for giving up smoking. A questionnaire survey was conducted on dental students from November 2003 to February 2004. The subjects were 69 third-grade and 80 fifth-grade students of Tokyo Medical and Dental University.