en orthodontic orthodontic Original article Original article <div> <table align="center" hspace="0" vspace="0"> <tbody> <tr> <td style="padding: 0cm 12px; text-align: justify;" valign="top"><span style="font-size:13pt"><span new="" roman="" style="font-family:" times=""><b><span style="font-size:9.0pt"><span style="font-family:" verdana=""><span style="color:#2e74b5">Background and Aim</span></span></span></b><b><span style="font-size:9.0pt"><span style="font-family:" verdana=""><span style="color:#2e74b5">:</span></span></span></b><b> </b><span lang="EN" style="font-size:9.0pt"><span style="font-family:" verdana="">Formation of white spot </span></span><span style="font-size:9.0pt"><span style="font-family:" verdana="">lesions, due to </span></span><span lang="EN" style="font-size:9.0pt"><span style="font-family:" verdana="">plaque accumulation and bacterial biofilm growth, is a common complication in orthodontic treatment. The </span></span><span style="font-size:9.0pt"><span style="font-family:" verdana="">present</span></span><span lang="EN" style="font-size:9.0pt"><span style="font-family:" verdana=""> study </span></span><span style="font-size:9.0pt"><span style="font-family:" verdana="">aimed to</span></span><span lang="EN" style="font-size:9.0pt"><span style="font-family:" verdana=""> compare the antibacterial properties of an orthodontic composite containing silver (Ag) and amorphous tricalcium phosphate (ATCP) nanoparticles against <i>Streptococcus mutans </i>(<i>S. mutans</i></span></span><span style="font-size:9.0pt"><span style="font-family:" verdana="">). &nbsp;</span></span></span></span><br> <span style="font-size:13pt"><span new="" roman="" style="font-family:" times=""><b><span style="font-size:9.0pt"><span style="font-family:" verdana=""><span style="color:#2e74b5">Materials and Methods:</span></span></span></b> <span lang="EN" style="font-size:9.0pt"><span style="font-family:" verdana="">In this in vitro study, 0.3% </span></span><span style="font-size:9.0pt"><span style="font-family:" verdana="">w/w</span></span><span lang="EN" style="font-size:9.0pt"><span style="font-family:" verdana=""> Ag nanoparticles and 3% </span></span><span style="font-size:9.0pt"><span style="font-family:" verdana="">w/w</span></span><span lang="EN" style="font-size:9.0pt"><span style="font-family:" verdana=""> ATCP nanoparticles were added to Transbond XT orthodontic composite. Totally, 48 composite discs were fabricated in three groups</span></span><span dir="RTL" lang="FA" style="font-size:9.0pt">) </span><span lang="EN" style="font-size:9.0pt"><span style="font-family:" verdana="">n=16). The experimental groups included composite specimens containing nanoparticles and the control group included composite specimens without nanoparticles. </span></span><span style="font-size:9.0pt"><span style="font-family:" verdana="">The antibacterial effects of composite discs with and without nanoparticles against </span></span><i><span lang="EN" style="font-size:9.0pt"><span style="font-family:" verdana="">S. mutans</span></span></i><span lang="EN" style="font-size:9.0pt"><span style="font-family:" verdana=""> (ATCC 35668)</span></span><span style="font-size:9.0pt"><span style="font-family:" verdana=""> in the three groups were assessed by the direct contact test after 24 hours and 30 days. The number of bacterial colonies was visually counted</span></span><span style="font-size:9.0pt"><span style="font-family:" verdana=""> in the three groups and compared. Data were analyzed by one-way ANOVA and Duncan&#39;s multiple comparisons test. </span></span><span style="font-size:9.0pt"><span style="font-family:" verdana="">P-values under 0.05 were considered significant. </span></span></span></span><br> <span style="font-size:13pt"><span new="" roman="" style="font-family:" times=""><b><span lang="EN" style="font-size:9.0pt"><span style="font-family:" verdana=""><span style="color:#2e74b5">Results: </span></span></span></b><span lang="EN" style="font-size:9.0pt"><span style="font-family:" verdana="">The antibacterial properties of nano-composites significantly increased in both experimental groups of composites containing Ag and ATCP nanoparticles, </span></span><span style="font-size:9.0pt"><span style="font-family:" verdana="">compared to the control group</span></span><span lang="EN" style="font-size:9.0pt"><span style="font-family:" verdana=""> (P<0.001). The highest antibacterial activity was observed in the orthodontic composite containing ATCP nanoparticles</span></span><span style="font-size:9.0pt"><span style="font-family:" verdana="">.</span></span></span></span><br> <span style="font-size:13pt"><span new="" roman="" style="font-family:" times=""><b><span style="font-size:9.0pt"><span style="font-family:" verdana=""><span style="color:#2e74b5">Conclusion:</span></span></span></b> <span lang="EN" style="font-size:9.0pt"><span style="font-family:" verdana="">Addition of <a name="_Hlk135909738">Ag and ATCP</a> nanoparticles to orthodontic light-cure composite increases its antibacterial activity against <i>S. mutans</i></span></span><span style="font-size:9.0pt"><span style="font-family:" verdana="">. &nbsp;</span></span></span></span></td> </tr> </tbody> </table> </div> Anti-Bacterial Agents, Composite Resins, Nanoparticles, Silver, Streptococcus mutans 257 264 http://jrdms.dentaliau.ac.ir/browse.php?a_code=A-10-1175-1&slc_lang=en&sid=1 Zahra Tavakolinejad tavakoli@gmail.com 100319475328460011474 100319475328460011474 No Department of Orthodontics, Faculty of Dentistry, Rafsanjan University of Medical Sciences, Rafsanjan, Iran Mahmood Sheikh Fathollahi Fathollahi@gmail.com 100319475328460011475 100319475328460011475 No Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran farzaneh Mirzaei mirzaei.elham2072@gmail.com 100319475328460011476 100319475328460011476 No Department of Parasitology and Mycology, School of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran Farzaneh Mirzaei 100319475328460011477 100319475328460011477 No Department of Laboratory Sciences, School of Paramedicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran Elham Mirzaei mirzaei.elham2072@gmail.com 100319475328460011478 0000000289952774 Yes Private Dentistry Practice, Yazd, Iran