Oral facial muscle weakness affects the structures of the oral mechanism and surrounding facial muscles that impacts the modalities of speech production and feeding/mastication. Speech production requires the integration of several systems one of which being neuromuscular motor output. If the muscles of the oral mechanism (mouth) and surrounding facial muscles do not have adequate strength, they are unable to perform the fine motor movements necessary for speech and feeding/mastication. Oral facial muscle weakness can influence affect, the face at rest, and the ability to make facial expressions.
The production of speech requires the articulation of sounds to be executed through the precise movements of speech structures within the musculature of the oral mechanism including the jaw, lips, cheeks, tongue and palate. When the muscles of this mechanism (such as muscles of the lips) are weakened, they are unable to make the precise contact necessary to make sounds such as bilabials /m,b,p,w/.
Oral facial muscle weakness affects feeding as the mouth and muscles of the mouth plays an integral part in the process of eating by containing the food within the mouth, chewing, and preparing the food for swallowing. Weakness to any of the muscles required for this process can result in deficits with feeding and swallowing (Dysphagia). Difficulty with straw drinking, drinking from an open cup or managing/manipulating food within the mouth is characteristic of an oral facial muscle weakness.
Oral facial muscle weakness not only affects feeding and swallowing but also can be problematic for non-speech tasks that require motor movements from the oral facial musculature such as the lips for actions such as blowing, puckering and smiling. These individuals may also have difficulty performing one or more of these movements in tandem. Individuals with oral facial muscle weakness may present with reduced muscle strength, reduced speed of movement of the muscle, reduced range of movement of the muscle, poor dissociation (independent movement) of the structures required for speech, reduced accuracy of the muscle movement, and diminished muscle tone. These deficits perceptually affect speech and can affect an individual’s ability to be understood by others when speaking.
Oral facial muscular weakness can co-occur with a variety of disorders such as dysarthria, cerebrovascular accidents (CVA), oral myofuntional disorders, multiple sclerosis, myasthenia gravis, muscular dystrophy, Bell’s palsy or they can be iatrogenic, meaning to relating to an illness cause by medical examination or treatment.
Assessment for oral facial muscle weakness can be conducted through subjective measures, instrumentation and biofeedback methods, and standardized measures administered by a trained Speech Language Pathologist. Tools and oral motor treatment protocols are used to teach dissociation, grading of the muscles of the jaw that are necessary for safe feeding and the production of speech. Treatment of oral facial muscle weakness involves several methods targeted at increasing the strength of the muscles of the oral mechanism through oral motor exercises, biofeedback methods and extinguishing behaviors that promote oral muscle facial weakness such as prolonged bottle, pacifier and sippy cup use.
Should you feel you fit the criteria of anything described or have any further questions relating to oral facial muscle weakness please contact one of our local offices to arrange an evaluation or to speak with one of our trained speech language pathologists.
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