In vitro dermal absorption and metabolism of D&C red no. 17 in human and porcineskin.

D&C red no. 17 is approved for use in externally applied drug and cosmetic applications, in amounts consistent with good manufacturing practice. Concerns about the safety of the color additive (1-[4-phenylazophenylazo]-2-napthol (PAN) is the primary color constituent) have been raised due to potential metabolic cleavage of PAN to yield 4-aminoazobenzene.

Strain gauge method for measuring polymerization contraction of composite restoratives.

Post-gel polymerization contraction of composite restoratives produces a volumetric change in phase with the development of a modulus of elasticity and distributes contractile stresses through the resin hard tissue interface into the tooth. A new method for monitoring the polymerization contraction of composite restoratives utilizes electrical resistance strain gauges. The strain gauge system was calibrated with dial gauge measurements of the bulk expansion of gypsum products.

The wear of enamel when opposed by ceramic systems.

The wear of enamel when opposed by different ceramic systems was investigated by use of an artificial oral environment. Cerestore, Dicor, and Ceramco discs were opposed by recently extracted natural teeth. The samples were exposed to 300,000 defined masticatory cycles under physiologic conditions.