What Is "Myo"?
The term "myo" is shorthand used in clinical settings to refer to the field of orofacial myology and the disorders it addresses. To understand it fully, break down the terminology:
What Is an Orofacial Myofunctional Disorder (OMD)?
According to the definition provided by the International Association of Orofacial Myology (IAOM), an OMD includes one or more of the following patterns:
An OMD includes: abnormal labial-lingual rest posture, bruxism (teeth grinding), poor nasal breathing, tongue protrusion while swallowing, poor mastication and bolus management, atypical oral placement for speech, lip incompetency, and digit habits and sucking habits (such as nail biting). These conditions can co-occur with speech misarticulations.
In other words, an OMD is not a single condition but a category of disorders that affect how the muscles of the face and mouth function at rest and during purposeful movements like swallowing, speaking, and chewing.
OMDs in SLP Practice
Because OMDs frequently co-occur with speech misarticulations and feeding difficulties, they are directly relevant to the clinical caseloads of speech-language pathologists. SLPs with training in orofacial myology are positioned to identify OMD patterns, understand how they may be contributing to a client's speech or feeding profile, and deliver targeted intervention.
Common presentations that may indicate an underlying OMD include:
- Tongue thrust swallowing - tongue protrudes forward or to the sides during the swallow
- Low tongue rest posture - tongue rests on the floor of the mouth rather than the palate
- Lip incompetency - lips do not close at rest, often associated with open mouth posture
- Mouth breathing - habitual oral breathing rather than nasal breathing at rest
- Digit habits - thumb sucking, nail biting, or other oral habits that affect oral-facial structure over time
- Bruxism - teeth grinding, which can impact jaw and bite development
How OMDs Relate to Speech and Articulation
The co-occurrence of OMDs with speech misarticulations is well-documented. When the tongue, lips, or jaw are not functioning with typical strength, coordination, or resting posture, the precision movements required for accurate speech production are compromised.
For SLPs, this means that treating a client's articulation errors without addressing the underlying myofunctional pattern may result in partial or temporary gains. Incorporating an OMD lens into your evaluation can help you identify when a structural or functional pattern is maintaining the error.
Next Steps for SLPs
If you are new to orofacial myology, TalkTools offers ASHA-approved continuing education designed specifically for SLPs who want to understand and address OMDs in their caseload.