Journal of AdvancedMedical and Dental Sciences Research

Background: The commonly used models to evaluate orthodontic tooth movement(OTM)in humans are canine retraction, lower anterior de-crowding, premolar buccal/apical movement, incisor apical movement, en-mass retraction, mesial/distal movement of molars and dental expansion.In therapeutic extraction cases, closure of first premolar space is a major step; hence earlier researchers have focused their attention on canine retraction to evaluate OTM. Objective: Studying OTM by considering as much as possible key factors that might have an effect on OTM is important and hence this review aimed to discuss whether the well-studied confounding variables had been considered when evaluating tooth movement in canine retraction studies. Method-Data source: Literature search had been carried out in the PubMed and Cochrane central library database using an appropriate search strategy together with hand searching. Study selection: A total of 47 articles were scrutinized from 418 clinical trials that met the stringent inclusion and exclusion criteria. Data extraction: Two authors independently extracted the data from each article with a pre-defined data field and the extracted data was finalized by the third author. Results: There is a presence of heterogeneity among the studies. Few studies have given adequate attention to well-studied confounding variables. Conclusion: The present review reveals that the factors that influence the tooth movement are vast and hence the outcomes of these studies should be viewed cautiously. Key words: Confounding factors, OTM, Canine retraction.