The technique for a comprehensive review aimed at assessing the antibacterial properties of cinnamon essential oil (CEO) on the oral microbiota through in vitro investigations is presented in this publication. This evaluation is registered with PROSPERO using registration number CRD42024577599 in accordance with PRISMA criteria. The review aims to address the effectiveness of CEO in modulating both bacterial and fungal populations in the oral cavity. The focus will be on how different types of cinnamon (Cinnamomum verum, Cinnamomum zeylanicum, Cinnamomum cassia) affect microbial concentrations, with primary outcomes including minimum inhibitory concentrations (MIC) and minimum fungicidal concentrations (MFC). Secondary outcomes will involve comparing the efficacy of CEO against various pathogens and determining methodological variations across studies. A thorough literature search will be carried out using a number of databases, including PubMed, SCOPUS, DOAJ, and Google Scholar, with each author assigned a distinct search task. The selection of articles will be managed using established assessment criteria, and data will be synthesized narratively, focusing on both antibacterial and antifungal effects of CEO. The review will also assess clinical and methodological heterogeneity, evaluating the risk of bias using the ROBINS-E tool and the certainty of evidence with the GRADE approach. The anticipated results aim to clarify CEO’s role in oral health, highlight methodological inconsistencies, and offer recommendations for future research. By synthesizing evidence from various studies, this review will contribute to understanding the potential applications of CEO in preventing and managing oral diseases, addressing gaps in current research, and providing clearer guidance for clinical practice.
