RESUMEN
Malocclusion represents the clinically observable endpoint of numerous genetic and environmental influences. Oral Myofunctional Therapy (OMT) aims to treat malocclusions by improving the oral environment through re-education of musculature and respiratory patterns. Although the concept of OMT has existed since the early part of the 20th Century, many of its purported benefits for the treatment of malocclusion remain undemonstrated in the scientific literature. However, a more recent application of OMT for the treatment of Obstructive Sleep Apnoea (OSA) suggests some benefits, although more research is needed to clarify this effect. Prefabricated functional appliances (PFAs) are sometimes advocated as part of myofunctional training programs. In the past decade, controlled clinical investigations have demonstrated that PFAs can improve Class II Division 1 malocclusions in compliant patients. Compared with traditional functional appliances, PFAs might be more cost effective; however, this must be balanced against compliance problems and evidence suggesting that other types of functional appliances might give better treatment results in a comparable time frame.