A number of developmental changes occur in eating patterns from infancy through childhood. Initially a primitive reflexive process, deglutition develops into a complex, integrated voluntary/reflexive process. The movements of the tongue, lips and mandible are easily observed to undergo a transformation from synergistic, undifferentiated movements in the infant, to differentiated and refined movements required for biting, chewing, bolus formation and propulsion in the toddler and young child. This transformation is also crucial for the development of higher levels of articulatory precision and coordination required for verbal communication. This developmental process does not always occur in individuals exhibiting orofacial myofunctional disorders. This article will review current research in this area as well as describe how to evaluate for normal tongue, lip and jaw differentiation, and present exercises to develop these skills, which are necessary for successful outcomes in orofacial myofunctional treatment.
Meyer, P. G. (2000). Tongue lip and jaw differentiation and its relationship to orofacial myofunctional treatment, International Journal of Orofacial Myology, 26 (1), 38-46.