Comment on

• Early treatment for Class II Division 1 malocclusion with the Twin-block appliance: a multi-center, randomized, controlled trial.

  O'Brien K, Wright J, Conboy F, Appelbe P, Davies L, Connolly I, Mitchell L, Littlewood S, Mandall N, Lewis D, Sandler J, Hammond M, Chadwick S, O'Neill J, McDade C, Oskouei M, Thiruvenkatachari B, Read M, Robinson S, Birnie D, Murray A, Shaw I, Harradine N, Worthington H. O'Brien K, et al. Am J Orthod Dentofacial Orthop. 2009 May;135(5):573-9. doi: 10.1016/j.ajodo.2007.10.042. Am J Orthod Dentofacial Orthop. 2009. PMID: 19409339 Clinical Trial.