Abstract: Described is apparatus and a method for measuring the integrity of coated paper, which apparatus comprises, a reservoir for a test liquid, e.g., water, retaining means for holding a sample of coated paper which is in liquid communication with the test liquid reservoir, means for applying ultrasonic energy to the sample of coated paper, photoelectric means for continuously measuring the turbidity of the test liquid, the photoelectric means being in liquid communication with the test liquid reservoir and the paper sample, recording means electrically connected to the photoelectric means for continuously recording the turbidity measurements, and means, including pumping means, for circulating test liquid between the reservoir, photoelectric means and paper sample retaining device.

Abstract: The compounds of the present invention are linear and branched dextrans having a plurality of their glucose units modified at the 3-position ring carbon with groups selected from the class consisting of keto, amino, halo, benzyl, alkyl, sulfonyl, carboxyl and hydrogen. The modified dextrans reduce and/or modify activity of glucosyltransferase enzymes (GTF) which are produced by oral strains of Streptococcus mutans bacteria. GTF enzymes mediate oral biosynthesis of plaque-forming glucose polymers (glucans) from ingested sucrose. Therefore, the dextrans of the present invention, which reduce and/or modify activity of GTF enzymes, are useful in reducing the formation of dental plaque. The present invention is further directed to a dental health method comprising the step of contacting the oral cavity with linear or branched dextran compounds having a plurality of their glucose units modified at the 3-position carbon with a group such as keto, amino, halo, benzyl, alkyl, sulfonyl, carboxyl or hydrogen.