The incidence of orofacial myofunctional disorders (OMD) has been investigated in several populations, including the general population, orthodontic patients, preschool children, and elementary school children. However, there has not been a systematic study of the prevalence of OMO among school children receiving speech and language services through the public schools. The American Speech-Language-Hearing Association (ASHA) has recognized a need for basic descriptive research regarding the various components of OMO and the interaction of those components with each other and with speech and language disorders. Therefore, the present study was designed to: 1) provide data regarding the incidence rates of OMO among children identified with speech and language disorders in grades kindergarten through six, and 2) investigate possible correlational relationships between the presence of various components of OMO with each other and with the presence of speech and/or language disorders. Two hundred children in grades kindergarten through six from various school districts in Fresno County, California were tested for the presence of various OMO components through examination of the orofacial complex. The resulting data was subjected to statistical analysis to determine the percentages of occurrence, and the possible relationships among various OMO variables were explored through cross tabulations and the Pearson Chi-square formula.
Wadsworth, S. D., et al. (1998). The prevalence of orofacial myofunctional disorders among children identified with speech and language disorders in grades kindergarten through six, International Journal of Orofacial Myology, 24 (1), 1-19.