title: Antimicrobial effects of silver zeolite, silver zirconium phosphate silicate and silver zirconium phosphate against oral microorganisms.
abstract: OBJECTIVE
  To evaluate the antimicrobial activities of silver inorganic materials, including silver zeolite (AgZ), silver zirconium phosphate silicate (AgZrPSi) and silver zirconium phosphate (AgZrP), against oral microorganisms. In line with this objective, the morphology and structure of each type of silver based powders were also investigated.
  
  
  METHODS
  The antimicrobial activities of AgZ, AgZrPSi and AgZrP were tested against Streptococcus mutans, Lactobacillus casei, Candida albicans and Staphylococcus aureus using disk diffusion assay as a screening test. The minimum inhibitory concentration (MIC) and minimum lethal concentration (MLC) were determined using the modified membrane method. Scanning electron microscope and X-ray diffraction were used to investigate the morphology and structure of these silver materials.
  
  
  RESULTS
  All forms of silver inorganic materials could inhibit the growth of all test microorganisms. The MIC of AgZ, AgZrPSi and AgZrP was 10.0 g/L whereas MLC ranged between 10.0-60.0 g/L. In terms of morphology and structure, AgZrPSi and AgZrP had smaller sized particles (1.5-3.0 µm) and more uniformly shaped than AgZ.
  
  
  CONCLUSIONS
  Silver inorganic materials in the form of AgZ, AgZrPSi and AgZrP had antimicrobial effects against all test oral microorganisms and those activities may be influenced by the crystal structure of carriers. These results suggest that these silver materials may be useful metals applied to oral hygiene products to provide antimicrobial activity against oral infection.
authors.affiliation: Faculty of Science, Mahidol University, Thailand.
authors.forename: Sirikamon
authors.initials: S
authors.lastname: Saengmee-Anupharb
authors.forename: Toemsak
authors.initials: T
authors.lastname: Srikhirin
authors.forename: Boonyanit
authors.initials: B
authors.lastname: Thaweboon
authors.forename: Sroisiri
authors.initials: S
authors.lastname: Thaweboon
authors.forename: Taweechai
authors.initials: T
authors.lastname: Amornsakchai
authors.forename: Surachai
authors.initials: S
authors.lastname: Dechkunakorn
authors.forename: Theeralaksna
authors.initials: T
authors.lastname: Suddhasthira
mesh_terms: D000890:Anti-Infective Agents / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects*; D002176:Candida albicans / Q000187:drug effects*; D008826:Microbial Sensitivity Tests; D011208:Powders / Q000494:pharmacology; D018030:Silver Compounds / Q000494:pharmacology*
chemical_list: D000890:Anti-Infective Agents; D011208:Powders; D018030:Silver Compounds
keywords: Oral microorganisms; Silver zeolite; Silver zirconium phosphate; Silver zirconium phosphate silicate