Drooling, or loss of saliva from the mouth, may occur for a variety of reasons. Gum or tooth disease, upper respiratory infections, sinus infections, allergies, middle ear infections, gastroesophageal reflux, medications, mouth breathing, body position, level of activity, intensity of concentration, and level of alertness may affect control of secretions and may result in drooling. Abnormal patterns of movement or muscle weakness for the lips, cheeks, jaw and tongue may also result in drooling. The focus of this article is drooling due to abnormal patterns of movement or muscle weakness, both of which may occur in individuals with low muscle tone.
To effectively and efficiently control oral secretions, the muscles and structures of the oral areas must constantly make subtle adjustments, twenty four hours a day. The sensory awareness at the lower cheeks, gums and lips must be present to detect the small changes in pressure on these tissues, which occur as saliva leaves the salivary ducts and enters the mouth. Range of cheek movement and lip movement for closure is necessary to maintain the negative intraoral seal during oral transit for swallowing. Lip power must be adequate to maintain the lips in a closed position during the swallow. The posterior cheek muscles must squeeze in toward the teeth and gums to shift the saliva to the center of the mouth for swallowing. The jaw must elevate to support the midblade of the tongue as it lifts up to contact the hard palate and propel the saliva into the pharynx. The soft palate must elevate during the swallow to close the nasal cavity and to maintain a negative pressure seal within the mouth.
Humans secrete an average of .5 to 1 Liter of saliva a day and .5 ml per minute during sleep. Due to the quantity of secretions, and the many coordinated patterns of muscle movement needed to swallow the saliva consistently, conscious control of secretions is not possible for anyone during waking hours, and certainly is not possible during sleep. For this reason, interventions emphasizing conscious control of saliva usually show poor results over time, and may result in undue frustration for the individual. Medications or surgery which reduce the amount of saliva produced, without addressing any underlying oral motor issues, offer partial solutions, but are complicated with potentially serious side effects. Surgical interventions are considered permanent and irreversible. Before proceeding with either of these options, a six-month trial of oral motor therapy is recommended.
To determine the muscle areas involved, a baseline of the components of muscle movement must be determined. These components include response to pressure and movement, range of movement, variety of movement, strength of movement, and control of movement. The areas assessed include the lips, cheeks, jaw, tongue and soft palate. Observation of the face at rest, and during activities such as eating, drinking, talking, and during change in facial expression are important. The structures of the face and mouth should be inspected visually for alignment and symmetry. In addition to observation, the lips, cheeks, jaw, tongue and soft palate can be manipulated manually, using the Beckman Oral Motor protocol, to add data regarding the components of movement listed above. This is especially important if the individual is nonverbal, on nonoral intake, or cannot follow commands. Findings from this baseline will yield data critical to the design of an effective intervention program.
The focus of oral motor intervention will be determined by the baseline assessment. Some examples of interventions might include increasing sensory awareness at the gums and inner lower cheeks, increasing passive range of cheek and lip movement, increasing posterior cheek strength, increasing lip strength at the sides and center of the upper and lower lips, increasing internal jaw strength, increasing soft palate activation, and increasing the variety of intrinsic tongue muscle movements. Drooling may still occur intermittently, especially during the occurrence of teething, gum or tooth disease, upper respiratory infections, sinus infections, allergies, middle ear infections, gastroesophageal reflux, mouth breathing, increased level of activity, increased level of concentration, or decreased level of consciousness. The overall occurrence of drooling is reduced due to the increased internal oral motor control the individual has developed. Function is the focus of the treatment outcome.