Biochemical mediators during active and retentive phases of tooth movement in orthodontic patients – a scoping review

Venkateswaran AnanthanarayananSridevi Padmanabhan^*

• Sri Ramachandra Institute of Higher Education and Research, Chennai, India

Word count: 349 Introduction: Crowding or spacing of teeth will impair oral hygiene maintenance and therefore lead to a poor oral health and nutrition. Orthodontic treatment will align the teeth and establish a proper occlusion, both of which are essential in the integrity of oral health and nutrition. Despite advancements in orthodontic treatment, relapse (teeth returning to the previous position) remains a major challenge. Previously, collagen turnover, then further studies, suggested extracellular matrix proteins such as tyrosine protein kinase (TEC protein) play a more significant role due to their exclusive presence during the retention phase. While extensive research exists on OTM, fewer studies have explored biochemical mediators during retention. The primary objective of this scoping review is to identify biochemical mediators at different timelines during OTM and relapse and address gaps so orthodontists may attempt to restrain the mediators thereby restoring oral health and nutrition. Method: This scoping review complied with the PRISMA-ScR guidelines. The search terms used were MESH terms and Boolean terminology. The search was conducted until July 2023 across five databases; PubMed, Scopus, Medline, Embase, and Google Scholar, including gray literature and unpublished data. The resulting numbers of articles (120) were chosen for the scoping review after matching with the framed inclusion and exclusion criteria (distributed as 113 and 7 studies for active and retentive phases respectively). The two reviewers resolved discrepancies through discussion. Any points of disagreement or conflict in the conducted search were escalated to the third senior reviewer, whose judgment was final. Results: The extraction of relevant data was independently performed by the two reviewers. The following data were analyzed: author name, journal, year of publication, type of study, sample size, sample site, type of biomarker assessed, and stage of orthodontic treatment. Queries pertaining to a particular study were clarified by contacting the lead author. These data were then shared with a third senior reviewer to streamline and finalize the data. Conclusions: The literature on biomarkers of tooth movement is exhaustive. However, studies on biomarkers during the retention phase are limited, and more exploration is needed. Registration: Registered in the Open Science Framework (https://osf.io/sh6u5)