The antibacterial activity of three iodine-containing compounds was determined for strains of four dental plaque-forming microorganisms, using an in vitro preclinical plaque model system. Solutions of inorganic iodine, povidone-iodine, and Wescodyne were tested for antiplaque activity against preformed plaques of a number of strains of Streptococcus mutans, Streptococcus sanguis, Actinomyces viscosus , and Actinomyces naeslundii . Solutions of inorganic iodine were more effective as antiplaque agents, with respect to minimal bactericidal concentration and time and frequency of treatments, than solutions of Wescodyne and povidone-iodine. Inorganic iodine appeared to be particularly effective against the most cariogenic ( S. mutans ) and periodontopathic ( A. viscosus ) organisms while allowing survival of the least orally pathogenic plaque-forming microorganism ( S. sanguis ). It is suggested that topical application of solutions of inorganic iodine may be useful in controlling dental caries and actinomyces-associated periodontal disease.

3-O-methylmannose isolated from Coccidioides immitis was characterized by gas chromatographic comparison of derivatives with those of synthetic 3-O-methylmannose. Gas chromatographic behavior of three derivatives of the natural and synthetic sugars was identical.3-O-methylmannose has been identified in Streptomyces griseus (2), Escherichia coli 08 (3), Klebsiella type K 57:05 (3), and Klebsiella types 2 and 6 (Gormus and Wheat, unpublished data) and was tentatively identified in Coccidioides immitis (5). The present work documents characterization of the C. immitis sugar as 3-0-methylmannose.The naturally occurring methylated sugar was obtained from pooled, dialyzed culture filtrates of C. immitis Silveira strain. The fungus was grown in glucose-yeast dialysate medium in a shaking broth culture for 3 days at 37 C. Culture filtrate (spent medium) was separated from the mycelial mat by filtration through Whatman no. 1 paper on a Buchner funnel. Culture filtrate solubles were passed through a Selas candle (porosity 03) to insure sterility, dialyzed against deionized water, and lyophilized. The lyophilized retentate (150 mg) was hydrolyzed with 15 ml of 2 N hydrochloric acid for 2 hr at 100 C, and acid was removed by distillation under reduced pressure. The hydrolysate was deionized with Dowex 50-H+ and then with Dowex 1-HC03-, concentrated, and then streaked on six thin-layer plates coated with a 0.5-mm layer of microcrystalline cellulose (Machery, Nagel & Co.). Glucose and synthetic (1) 3-0-methyl-Dmannose were run on either side of the hydrolysate streak. The plates were developed twice in n-butanol-acetic acid-water (5:1:2) and then sprayed with alkaline silver nitrate or Timell's reagent as described previously (5) to locate the standard sugars and the edges of the hydrolysate bands. Bands with RGIC values corresponding to synthetic 3-0-methylmannose were scraped from the plates and eluted with water. The slurry was filtered on Whatman no. 1 paper, and the filtrate was passed through a 0.45-Am filter disc (Milli-pore Corp.) before being lyophilized (yield, 4.1 mg, 2.7%).In an earlier report (5), tentative identification of the natural methylated sugar was made by thin-layer chromatography. Gas chromatography has now been used to compare several derivatives of the natural and synthetic sugars. The major peaks observed on gas-liquid chromatograms of the natural and synthetic preparations were found to be additive in all cases. The derivatives were prepared by (i) conversion of the sugars to their alditol acetates, (ii) preparation and acetylation of the methyl glycosides, and (iii) acetylation of the sugars without prior reduction.The alditol acetates were prepared by the method of Sawardeker et al. (4). For preparation of the acetylated methylglycosides, a 20-,ug sample of the sugar was heated under reflux for 2 hr with 1 ml of 2% methanolic hydrogen chloride. The solvent was removed in a rotary evaporator, and the residue was then heated at 138 C with 0.25 ml of an acetic anhydride-pyridine mixture (2:1, v/v) fo...

The bactericidal efficacy of seven cationic detergents was studied in vitro against intact preformed plaques of representative strains of four oral dental plaque-forming microorganisms: Streptococcus mutans, Streptococcus sanguis, Actinomyces viscosus, and Actinomyces naeslundii. Both absolute (plaque bactericidal index) and relative (chlorhexidine coefficient) indexes of antiplaque activity were established. Only cetyltrimethylammonium bromide was more efficacious than the reference agent, the bisbiguanide chlorhexidine, for the apparently more potent tooth-adherent cariogenic and periodontopathic elements, respectively, of the in vivo plaque microflora, S. mutans and A. viscosus.Control Qf dental plaque, which is associated with gingivitis and dental caries, may be achieved by topical applications of antimicrobial agents (11,18,19). Topical rather than systemic administration of such agents to supragingival plaque is indicated because of its dense, toothadherent nature and, importantly, because plaque is not bathed in blood or interstitial fluids but is exposed to the environment of the oral cavity.Cationic detergents have been known for a number of years to possess bactericidal and fungicidal properties (17). Cationic agents are also of interest because of potential reversible binding (substantivity) to anionic groups on oral mucous membranes (2,21,22,25,26), which could permit possible prolonged intraoral retention and sustained release of such cationic antiseptics. Recent studies have demonstrated modest in vivo and in vitro antiplaque activities of three quaternary ammonium detergents, namely, cetylpyridinium chloride, domiphen bromide, and benzylalkonium chloride (1,6,12,27,35). In those studies, however, the optimal conditions required for in vivo efficacy were not evaluated.In the work reported herein an examination of seven cationic detergents was undertaken with a view to establishing the optimal conditions likely to achieve maximal efficacy in vivo. These agents were assessed for their antiplaque activities against strains of four oral plaqueforming microorgansms by using an in vitro preformed-plaque model system (30, 31), and their potencies were compared on both absolute t Present address: