en عفوني Infectious disease پژوهشي Research <div style="text-align: justify;"><span style="font-size:11pt"><span style="line-height:normal"><span sans-serif="" style="font-family:Calibri,"><b><span style="font-size:12.0pt"><span new="" roman="" style="font-family:" times=""><span style="color:#2f5496">Background & Objectives:</span></span></span></b><span style="font-size:12.0pt"><span new="" roman="" style="font-family:" times=""> Due to the increasing trend of extensive antibiotic resistance among bacterial strains and side effects, seeking novel methods such as nanoparticles (NPs) is promising for infection eradication. </span></span></span></span></span><br> <span style="font-size:11pt"><span style="line-height:normal"><span sans-serif="" style="font-family:Calibri,"><b><span style="font-size:12.0pt"><span new="" roman="" style="font-family:" times=""><span style="color:#2f5496">Materials & Methods:</span></span></span></b><span style="font-size:12.0pt"><span new="" roman="" style="font-family:" times=""> Eighteen <i>Streptococcus mutans</i> (<i>S. mutans)</i> clinical isolates were collected from dental plaques. Moreover, <i>S. mutans</i> ATCC25175 standard strain was obtained from Pasteur institute of Iran. Following preparation of nanoparticles, their antibacterial effects were assessed compared to chlorhexidine. The nickel NPs (Ni-NPs) was prepared and its antibacterial effect was compared to the 12% chlorhexidine. The minimum inhibitory and bactericidal concentrations (MIC and MBC, respectively) of Ni-NP (dilution range: 0.125-64&micro;g/mL) were measured using broth microdilution method. </span></span></span></span></span><br> <span style="font-size:11pt"><span style="line-height:normal"><span sans-serif="" style="font-family:Calibri,"><b><span style="font-size:12.0pt"><span new="" roman="" style="font-family:" times=""><span style="color:#2f5496">Results:</span></span></span></b><span style="font-size:12.0pt"><span new="" roman="" style="font-family:" times=""> The nickel NPs (Ni-NPs) was prepared and its antibacterial effect was compared to the 12% chlorhexidine. The minimum inhibitory and bactericidal concentrations (MIC and MBC, respectively) of Ni-NP (dilution range: 0.125-64&micro;g/mL) were measured using broth microdilution method. The MIC and MBC levels of Ni-NP against the clinical isolates ranged 2-16&micro;g/mL and 4-16&micro;g/mL, respectively. These values against the <i>S. mutans</i> ATCC27175 standard strain included 4 and 8&micro;g/mL, respectively. Furthermore, the MIC and MBC of chlorhexidine against clinical isolates ranged 8-64 and 32-64&micro;g/mL, respectively, while both included 64&micro;g/mL against standard strain (p<0.001). </span></span></span></span></span><br> <span style="font-size:11pt"><span style="line-height:normal"><span sans-serif="" style="font-family:Calibri,"><b><span style="font-size:12.0pt"><span new="" roman="" style="font-family:" times=""><span style="color:#2f5496">Conclusions:</span></span></span></b><span style="font-size:12.0pt"><span new="" roman="" style="font-family:" times=""> The results of this study outlined that Ni-NPs exert efficient antibacterial effect at nontoxic concentrations compared to 12% chlorhexidine.</span></span></span></span></span></div> Dental caries, Streptococcus mutans, Nickel nanoparticles, Chlorhexidine, Antibacterial effect 167 174 http://jabs.fums.ac.ir/browse.php?a_code=A-10-1709-9&slc_lang=en&sid=1 Ali Bazrafkan علی بذرافکن 100319475328460027813 100319475328460027813 Yes Departments of Microbiology, Deputy of Research and Technology, Jahrom University of Medical Sciences, Jahrom, Iran روه میکروبیولوژی، آزمایشگاه تحقیقات مرکزی، دانشگاه علوم پزشکی جهرم، جهرم، ایران Farzan Modaresi فرزان مدرسی 100319475328460027814 100319475328460027814 No Departments of Microbiology, Deputy of Research and Technology, Jahrom University of Medical Sciences, Jahrom, Iran روه میکروبیولوژی، آزمایشگاه تحقیقات مرکزی، دانشگاه علوم پزشکی جهرم، جهرم، ایران Sahar Rostamifar سحر رستمی فر 100319475328460027815 100319475328460027815 No Oral and Dental Disease Research Center, Department of Oral & Maxillofacial Medicine, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran مرکز تحقیقات بیماری های دهان و دندان، گروه پزشکی دهان و فک و صورت، دانشکده دندانپزشکی، دانشگاه علوم پزشکی شیراز، شیراز، ایران Shekoufeh Atashpour شکوفه آتش پور 100319475328460027816 0009-0002-8249-9687 No Departments of Pharmacology, Advanced Medical Sciences and Technology, and Central Laboratory Research, Jahrom University of Medical Sciences, Jahrom, Iran گروه فارماکولوژی، علوم و فناوری پیشرفته پزشکی و تحقیقات آزمایشگاهی مرکزی، دانشگاه علوم پزشکی جهرم، جهرم، ایران Azita Azad آزیتا آزاد 100319475328460027817 100319475328460027817 No Oral and Dental Disease Research Center, Department of Oral & Maxillofacial Medicine, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran مرکز تحقیقات بیماری های دهان و دندان، گروه پزشکی دهان و فک و صورت، دانشکده دندانپزشکی، دانشگاه علوم پزشکی شیراز، شیراز، ایران Abdolmajid Ghasemian عبدالمجید قاسمیان 100319475328460027818 100319475328460027818 No Noncommunicable Diseases Research Center, Fasa University of Medical Sciences, Fasa, Iran مرکز تحقیقات بیماری‌های غیرواگیر، دانشگاه علوم پزشکی فسا، فسا، ایران