Littlewood, S. J., Tait, A. G., Mandall, N. A., and Lewis, D. H. (2001). The role of removable appliances in contemporary orthodontics. British Dental Journal, 191, 304–10. [DOI: 10.1038/sj.bdj.4801170] [PubMed: 11587502]
A readable and well-illustrated article.
Ward, S. and Read, M. J. F. (2004). The contemporary use of removable appliances. Dental Update, May, 215–7. [DOI: 10.12968/denu.2004.31.4.215] [PubMed: 15188527].
Another useful article.