A normal rest posture includes lips that remain closed. When the lips do
not meet at rest and the mentalis muscle strains during closing, this is known
as lip incompetence. This may be interrelated to tongue-thrusting,
digit-sucking or chronic airway obstruction from allergies or enlarged tonsils
or adenoids. Lip incompetence cannot only have negative cosmetic consequences,
but it can also lead to excessive drooling, messy eating, or dry mouth and
gingivitis if the patient is also mouth-breathing. The therapist works closely with the
necessary specialists such as ENT's and allergists to help resolve negative factors that could be contributing to OMD.