Abstract: This review aims to summarise the properties, interactions, biocompatibility and associated adverse reactions of the commonly used orthodontic materials in clinical practice. The recent years have seen the introduction of a variety of new orthodontic products necessitating the need for an all-inclusive training in the dental materials field. It is essential for orthodontists to have the basic knowledge about composition of these materials, their structure and properties. Clinically the interactions of orthodontic materials with the hard tissues in the oral cavity and with other dental materials can lead to the issue cytotoxicity and allergic reactions for both patients and doctors. The background about these interactions will allow the orthodontist to make correct material selections which will provide for adequate treatment mechanics and simultaneously equip him/her with the knowledge to deal with the complex effects of the orthodontic materials in the oral environment Several electronic databases were searched for relevant research and material regarding biocompatibility and interactions of the commonly used orthodontic materials in clinical practice.The Directory of Open Access Journals (DOAJ), meta Register of Controlled Trials, WHO, Digital Dissertations and Google Scholar were used to look for the relevant data. The references and citations of already existing reviews and articles on the issue of biocompatibilty were also searched. This review is mainly done to attain better knowledge about the biocompatibility of different materials that are used in the orthodontic practice and their associated effects.