**3. Etiology of sialorrhea**

impairment in the swallowing mechanism, all of which are necessary to move saliva from the oral cavity to the oropharynx and beyond [1]. Drooling is common in normally developed babies but subsides between the ages 15 and 36 months with the establishment of salivary continence. Sialorrhea after 4 years of age is generally considered pathologic. Pathologic sialorrhea may develop due to hypersalivation, together with numerous neurologic disorders including cerebral palsy (CP), Parkinson's disease (PD), and amyotrophic lateral sclerosis (ALS), or as an adverse effect of medications. In children, the most common cause of sialorrhea is CP, which persists in 10–38% of these patients. In adults, the most common cause of

Whatever the cause is, drooling is bothersome, resulting in physical and psychosocial complications. Physical complications include maceration of the skin around the mouth with secondary infection, bad odor, dehydration, speech disturbance, and interference with feeding. People with drooling are also at increased risk for aspiration of saliva, food, or fluids into lungs, particularly when the normal reflex mechanisms such as gagging or coughing are impaired. The psychosocial complications include isolation, barriers to education (such as an inability to share books or computer keyboards), increased dependency and level of care, damage to electronic devices, decreased self-esteem, and difficult social interaction [3]. Sialorrhea may have a significant negative impact on quality of life for both the patient and caregiver [1].

The major salivary glands include parotid, submandibular, and sublingual glands; the largest being the parotid gland. These glands secrete saliva, which has a major role in lubrication, digestion, immunity, and maintenance of homeostasis in the human body [2]. The salivary secretion of parotid, submandibular, and sublingual glands is controlled mainly by parasympathetic nervous system, although sympathetic innervation has a minor influence. The parasympathetic fibers originate in the pons and medulla, and they synapse in the otic and submandibular ganglia. Postganglionic fibers originating from the otic ganglion regulate secretory functions of the parotid gland, while the postganglionic fibers from the submandibular ganglion regulate secretory function of the submandibular and sublingual glands. Sympathetic innervation of these glands results in contraction of muscle fibers around the

Salivary secretion is regulated through a reflex arch that produces several actions. The afferent branch contains chemoreceptors in taste buds and mechanoreceptors in the periodontal ligament. Afferent innervations of cranial nerves V, VII, IX, and X carry impulses to salivary nuclei in the medulla oblongata. Efferent impulses are mainly parasympathetic as described above; they come from the chorda tympani nerve (a branch of the cranial nerve VII) and travel to the submandibular, sublingual, and other minor glands via lingual nerve (a branch of the

(a branch of cranial nerve IX), which travel through the fibers of auriculotemporal nerve (a

) and reach the gland [2].

). Efferent fibers to the parotid gland are supplied by lesser petrosal nerve

sialorrhea is PD with a rate of 70–80% [2].

38 Salivary Glands - New Approaches in Diagnostics and Treatment

**2. Physiology of salivation**

cranial nerve V<sup>3</sup>

branch of the cranial nerve V<sup>3</sup>

salivary ducts, which enhances the flow of saliva [3].

Sialorrhea associated with neurologic illnesses is generally caused by impaired swallowing due to impaired neuromuscular function. Efficient coordination of various structures, namely the oral cavity, pharynx, larynx, and esophagus, is required for the neuromuscular activity of swallowing. The coordination of these structures forms three phases; the oral phase is under voluntary control, followed by the pharyngeal and esophageal phases, which are involuntary. Spontaneous swallowing is essential for the control of drooling. In children with neurologic disorders, drooling is similarly the result of inefficient tongue and/or bulbar control, thus impaired swallowing, rather than hypersalivation [2].

In children, mental retardation and CP are the most common causes of sialorrhea. Roughly, one in three children with CP is reported to have some degree of sialorrhea. Sialorrhea in CP is caused by oral motor dysfunction, dysphagia, and intraoral sensitivity disorder. Though underestimated, sialorrhea has significant clinical and social consequences concerning the overall health of these children, including dysphagia, respiratory health, and socioemotional aspects of both the children and their caregivers [4]. In adults, PD is the most common etiology. Swallowing impairment, mostly in the oropharyngeal phase, is the major contributor to the pathophysiology of sialorrhea in PD patients, while an increase in the speed of salivary excretion might be a minor contributor. No increase in salivary production was demonstrated in scintigraphic studies in PD patients with sialorrhea, while the speed of salivary excretion of parotid glands in PD patients was significantly higher than normal controls with Tc-99 m scintigraphy [6]. Similarly, in ALS, sialorrhea is not caused by increased production of saliva, but by the inability to swallow secretions because of tongue spasticity, weakness of face, mouth and pharyngeal muscles, and loss of oropharyngeal coordination and function [5]. Less common neurologic causes of sialorrhea are pseudobulbar palsy, bulbar palsy, and stroke (**Table 1**).

#### **Systemic causes**


#### **Local causes**


#### **Physiological causes**

• Pregnancy

**Table 1.** Etiology of sialorrhea.

Increased secretion of saliva frequently develops due to inflammation, such as teething, dental caries, and oral cavity infections. Pregnancy is another significant cause of hypersecretion, usually related to hyperemesis gravidarum. It has an abrupt onset in the 2nd and 3rd week of conception with the rise of hormones and usually resolves during 2nd trimester [7]. Other causes of hypersecretion include side effects from medications (i.e., antipsychotics, tranquilizers, anticonvulsants, cholinergic agonists, and lithium), gastroesophageal reflux, toxin exposure (i.e., mercury vapor, poisonous spider bites, mushrooms, insecticides), and rabies [3, 8]. Clozapine, an antipsychotic used in schizophrenia, is a rather common cause of sialorrhea, which manifests in 30–80% of patients taking the drug. Hypersalivation usually develops early in the treatment course and is typically more prominent at night [9].

hypertrophy; nasal blockage, malocclusion, and jaw stability should be assessed. A neurological examination should be carried out investigating the level of alertness, swallowing ability, motor skills, and sensory dysfunction of the patient. The nutrition and hydration status, head

**Drooling severity Points** Dry (never drools) 1 Mild (wet lips only) 2 Moderate (wet lips and chin) 3 Severe (clothing becomes damp) 4 Profuse (clothing, hands, tray, objects become wet) 5

Sialorrhea: A Guide to Etiology, Assessment, and Management

http://dx.doi.org/10.5772/intechopen.82619

41

Never drools 1 Occasionally drools 2 Frequently drools 3 Constantly drools 4

Objective and subjective measures have been developed to quantify sialorrhea. The objective test methods include radioisotope scanning, collection cups strapped to the patient's chin for the measurement of salivary flow, and direct observation of saliva loss such as counting the number of napkins used daily to contain excessive saliva production, measuring the weight of the towels or dental cotton rolls [4, 10]. The importance of objective methods is that they seem to be more sensitive in detecting a reduction in sialorrhea or drooling than purely subjective assessments [11].

A variety of subjective scales for sialorrhea have been described. Subjective scales such as the drooling frequency and severity scale, the drooling rating scale, the drooling impact Scale, and visual analog scales can be given to patients or their caregivers to determine the qualitative and quantitative consequences of the severity and impact of sialorrhea [4]. The drooling frequency and severity scale is an easy comprehensive scale, which rates the severity of drooling on a five-point scale and the frequency of drooling on a four-point scale (**Table 2**) [12]. Subjective scales are useful and appropriate methods to measure changes in sialorrhea, because the impact on families, caregivers, and the patients themselves is of utmost impor-

The management of sialorrhea continues to be a challenge in spite of various effective treatment strategies to diminish saliva production. The flow of saliva from the oral cavity to the esophagus depends on numerous factors, such as cognitive and mental abilities, intact swal-

posture, and emotional state of the patient should also be evaluated [4, 10].

tance when assessing satisfaction with the effectiveness of any treatment [4].

lowing, oral sensibility, lip closure, and ability to keep the head upright [1].

**5. Management of sialorrhea**

**Drooling frequency**

**Table 2.** Drooling frequency and severity scale.

Anatomic abnormalities are usually not the only cause of sialorrhea; however, most of the time, they exacerbate other causative conditions. Macroglossia (enlarged tongue) and oral incompetence may cause salivary spilling. A constantly open mouth due to nasal blockage or malocclusion and other orthodontic problems may compound oral incompetence; treatment of nasal problems and orthodontic correction can alleviate sialorrhea. Surgical defects occurring after major head and neck surgeries may result in sialorrhea as well [3].

### **4. Assessment of sialorrhea**

Assessment of the severity of sialorrhea and its impact on the quality of life for the patient and the caregivers assist in establishing a prognosis and appropriate management of the problem. History should be taken from the patient and the caregiver to understand the etiology and severity of the situation and its impact on the daily life. Use of medications, language and communication skills, cognition, respiratory health, and presence of gastroesophageal reflux disease should be questioned. In physical examination, oral cavity should be examined for sores on the lip and chin, dental problems, tongue size and movement, and tonsillar


**Table 2.** Drooling frequency and severity scale.

Increased secretion of saliva frequently develops due to inflammation, such as teething, dental caries, and oral cavity infections. Pregnancy is another significant cause of hypersecretion, usually related to hyperemesis gravidarum. It has an abrupt onset in the 2nd and 3rd week of conception with the rise of hormones and usually resolves during 2nd trimester [7]. Other causes of hypersecretion include side effects from medications (i.e., antipsychotics, tranquilizers, anticonvulsants, cholinergic agonists, and lithium), gastroesophageal reflux, toxin exposure (i.e., mercury vapor, poisonous spider bites, mushrooms, insecticides), and rabies [3, 8]. Clozapine, an antipsychotic used in schizophrenia, is a rather common cause of sialorrhea, which manifests in 30–80% of patients taking the drug. Hypersalivation usually develops

• Neuromuscular/sensory dysfunction—cerebral palsy, Parkinson's disease, mental retardation, motor neuron

• Medication side effects—antipsychotics (clozapine), tranquilizers, anticonvulsants, anticholinesterases, lithium

• Anatomic—macroglossia, nasal blockage, oral incompetence, dental malocclusion, orthodontic problems, head

Anatomic abnormalities are usually not the only cause of sialorrhea; however, most of the time, they exacerbate other causative conditions. Macroglossia (enlarged tongue) and oral incompetence may cause salivary spilling. A constantly open mouth due to nasal blockage or malocclusion and other orthodontic problems may compound oral incompetence; treatment of nasal problems and orthodontic correction can alleviate sialorrhea. Surgical defects occur-

Assessment of the severity of sialorrhea and its impact on the quality of life for the patient and the caregivers assist in establishing a prognosis and appropriate management of the problem. History should be taken from the patient and the caregiver to understand the etiology and severity of the situation and its impact on the daily life. Use of medications, language and communication skills, cognition, respiratory health, and presence of gastroesophageal reflux disease should be questioned. In physical examination, oral cavity should be examined for sores on the lip and chin, dental problems, tongue size and movement, and tonsillar

early in the treatment course and is typically more prominent at night [9].

ring after major head and neck surgeries may result in sialorrhea as well [3].

**4. Assessment of sialorrhea**

**Systemic causes**

• Infection—rabies

**Physiological causes** • Pregnancy

**Local causes**

• Gastric—gastroesophageal reflux

• Oral Inflammation—teething

and neck surgical defects

**Table 1.** Etiology of sialorrhea.

disease (ALS), pseudobulbar/bulbar palsy, stroke

40 Salivary Glands - New Approaches in Diagnostics and Treatment

• Toxin exposure—mercury vapor, pesticides, snake poisoning, mushrooms

• Infection—dental caries, oral cavity infection, tonsillitis, peritonsillar abscess

hypertrophy; nasal blockage, malocclusion, and jaw stability should be assessed. A neurological examination should be carried out investigating the level of alertness, swallowing ability, motor skills, and sensory dysfunction of the patient. The nutrition and hydration status, head posture, and emotional state of the patient should also be evaluated [4, 10].

Objective and subjective measures have been developed to quantify sialorrhea. The objective test methods include radioisotope scanning, collection cups strapped to the patient's chin for the measurement of salivary flow, and direct observation of saliva loss such as counting the number of napkins used daily to contain excessive saliva production, measuring the weight of the towels or dental cotton rolls [4, 10]. The importance of objective methods is that they seem to be more sensitive in detecting a reduction in sialorrhea or drooling than purely subjective assessments [11].

A variety of subjective scales for sialorrhea have been described. Subjective scales such as the drooling frequency and severity scale, the drooling rating scale, the drooling impact Scale, and visual analog scales can be given to patients or their caregivers to determine the qualitative and quantitative consequences of the severity and impact of sialorrhea [4]. The drooling frequency and severity scale is an easy comprehensive scale, which rates the severity of drooling on a five-point scale and the frequency of drooling on a four-point scale (**Table 2**) [12]. Subjective scales are useful and appropriate methods to measure changes in sialorrhea, because the impact on families, caregivers, and the patients themselves is of utmost importance when assessing satisfaction with the effectiveness of any treatment [4].
