Amir Hossein Mirhashemi - Department of Orthodontics, Tehran University of Medical Sciences, Tehran, IR Iran
Niloofar Farahmand - Dentist, Tehran, IR Iran
Elahe Soltanmohamadi Borujeni - Department of Orthodontics, Tehran University of Medical Sciences, Tehran, IR Iran

Context One of the most important aims in orthodontic treatment is to apply a light continuous force to achieve maximum effective tooth movement with minimal side effects (optimal tooth movement). It is obvious that elastomeric chains are the most popular method of space closure, but they undergo force decay during time. Force decay behavior of elastomeric chains is influenced by various factors. It is crucial for every practitioner to know about these products and factors affecting them. Evidence Acquisition So we searched English articles published in Pubmed between ۲۰۰۵ - ۲۰۱۶ with keyword “orthodontics, elastomeric chain”. Results ۲۵ articles were selected for comprehensive reading according to the inclusion criteria. Some factors such as aging process, production technique, pre-stretching effect, design and type of chains, in-vivo effects and microbial contamination were discussed. Conclusions By reviewing these articles, we know more about force decay pattern of elastomeric chains. Most of articles said the same force decay pattern for these elastomeric products. We know more about environmental conditions affect their features. This can help practitioners to use chains , in a better way.