en عمومى General گزارش مورد case report <p><strong>Background:</strong> Dental caries is one of the most prevalent chronic human infections worldwide. It begins with bacterial adherence to the tooth surface and the formation of dental plaques. Among various microorganisms involved, mutans streptococci are the principal oral microorganisms involved in the initiation and development of dental caries. Cetylpyridinium chloride (CPC), a quaternary ammonium with a rapid bactericidal effect, is widely used as the active ingredient of antiseptic oral mouthrinses. Plants extracts are also extensively employed in oral hygiene products for their antimicrobial, anti-inflammatory, and astringent properties. The present study aimed to investigate the combined antibacterial activity of CPC in combination with two plant extracts that are extensively utilized in dental hygiene products.</p> <p><strong>Methods:</strong> The aerial parts of <em>Matricaria chamomile</em> and hydroalcoholic extracts of <em>Quercus infectoria</em> galls were prepared by maceration. Dried extracts were investigated for antibacterial activity against <em>Streptococcus</em> <em>mutans</em> by determining the minimum inhibitory concentrations (MICs). A checkerboard method was applied to investigate the combined antibacterial activity of CPC in the presence of <em>M. chamomile</em> aerial parts and <em>Q. infectoria</em> gall extracts.</p> <p><strong>Results:</strong> The results of this study indicated a synergistic effect between CPC and the hydroalcoholic extract of <em>Q. infectoria</em> galls. However, the presence of the extract of <em>M. chamomile</em> aerial parts had an antagonistic effect on the antibacterial activity of CPC against <em>S. mutans</em>.</p> Antagonism, Antiseptic mouthwash, Cetylpyridinium, Herbal, Matricaria, Synergism 57 62 http://ajpr.umsha.ac.ir/browse.php?a_code=A-10-2-73&slc_lang=en&sid=1 Fatemeh Hamidbeigi-Moghadam 1003194753284600345 1003194753284600345 No Department of Pharmaceutics, School of Pharmacy, Hamadan University of Medical Sciences, Hamadan, Iran Mahshid Hoseini 1003194753284600346 1003194753284600346 No Department of Pharmaceutics, School of Pharmacy, Hamadan University of Medical Sciences, Hamadan, Iran Shirin Moradkhani 1003194753284600347 1003194753284600347 No Department of Pharmacognosy, School of Pharmacy, Hamadan University of Medical Sciences, Hamadan, Iran Shabnam Pourmoslemi sh.moslem@umsha.ac.ir 1003194753284600348 1003194753284600348 Yes Department of Pharmaceutics, School of Pharmacy, Hamadan University of Medical Sciences, Hamadan, Iran