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The mineral group zeolites, also have vast adsorptive and absorptive capabilities through a rigid, porous, three-dimensional channel or tube in their basic cryalline structure. They are compositionally similar to clay minerals and also have a high cation exchange capacity (Baerlocher et al., 2007). With strong affinity for oxidized silver ions (Ag⁺), up to 40% (w/w), silver-exchanged zeolites have demonstrated antibacterial effectiveness against aerobic and anaerobic Gram-negative and Gram-positive bacterial pathogens, including Pseudomonas aeruginosa, Porphyromonas gingivalis, Prevotella intermedia, Staphylococcus aureus, Streptococcus mutans, and Streptococcus sanguis and have been used in various dental applications (Hotta et al., 1998; Kawahara et al., 2000; Matsuura et al., 1997). Another study investigated the mechanism of action of silver-exchanged zeolite and determined that physical contact with the bacterial cell, silver transfer into the cell, and/or the generation of reactive oxygen species attributed to the bactericidal activity of silver zeolite (Matsumura et al., 2003). However, while these inorganic products have antibacterial activity and low toxicity, issues related to the reduction of silver ions to elemental silver and subsequent loss of antibacterial effectiveness could be problematic (Li et al., 2002). Therefore, an oxidized form of Ag appears to be important for bactericidal activity of silver-exchanged zeolites.