Minimizing the Damaging Effects of Xerostomia

For many patients, xerostomia is simply a dry mouth. However, for those who are experiencing moderate-to-severe xerostomia, this condition impacts them daily. The implications for oral and systemic health from the absence of saliva can profoundly affect comfort and quality of life. As a dental professional, dental hygienists have the opportunity to be on the front lines of identifying xerostomia, resulting in the delivery of proactive treatment to minimize the damaging effects on the oral cavity. The first step in treating xerostomia effectively is to identify the condition accurately. The patient may initiate the conversation; however, the dental professional is often the one to identify the condition, utilizing both subjective and objective approaches.

Identification of Xerostomia

The Challacombe Scale was designed for the purpose of identifying and quantifying xerostomia. Developed through research led by Professor Stephen Challacombe at King's College London Dental Institute, the scale is numbered 1 to 10, with summated scoring dictating the severity of the condition and treatment course. The observed clinical indicators provide dental professionals with direction to identify the severity of xerostomia.

The clinical features indicating oral dryness are ¹:

1. The mouth mirror sticks to the buccal mucosa
2. The mouth mirror sticks to the tongue
3. The saliva is frothy
4. No saliva pooling in the floor of the mouth
5. Tongue shows generalized shortened papillae
6. Altered gingival architecture (gingival tissues appear smooth)
7. Glassy appearance of oral mucosa especially palatal tissues
8. Tongue is lobulated or fissured
9. Cervical caries affecting more than 2 teeth
10. Debris on palate or adhering to dentition

An additive score of 1 to 3 indicates mild xerostomia: Lifestyle changes such as attention to hydration and minimal treatment with continued monitoring are sufficient to address this level. An additive score of 4 to 6 indicates moderate xerostomia: Treatment will be directed based on identified etiologic pathways and may include salivary substitutes, topical fluoride varnish, xylitol chewing gum or mints, and remineralization toothpastes. Regular professional care and monitoring of caries activity and periodontal status are vital.

Finally, an additive score of 7 to 10 indicates severe xerostomia. Salivary substitutes and stimulants, topical fluoride varnish, xylitol, and remineralization toothpastes are recommended. Referral for investigation into etiologic pathways such as Sjögren's syndrome or other autoimmune disease presence is required. Regular professional care and monitoring at this stage are critical to continue to evaluate the effects of xerostomia on oral disease. 

Additional clinical features that may direct the identification of a xerostomic condition include multiple sites of cervical dentinal hypersensitivity, accelerated wear and erosion, inadequate retention of full upper dentures, and poorly mineralized calculus (or no calculus) on the lingual aspects of mandibular anteriors despite the presence of plaque. 

In addition to these clinical indicators, a subjective interview to reveal signs and symptoms can be particularly helpful in addressing the comprehensive needs of the patient. These questions aid in establishing the level of xerostomic severity the patient is experiencing:

1. Does your mouth often feel dry or sticky?
2. Do you regularly drink water, eat crushed ice, or drink other fluids to keep your mouth moist?
3. Do you ever feel self-conscious of having bad breath?
4. Do you wake up in the middle of the night with a dry mouth? 
5. Do you have difficulty speaking, swallowing, or eating because your mouth or throat is dry?
6. Do you have difficulty swallowing or eating without something to sip or drink?
7. Does food frequently stick in your teeth?
8. Has the consistency or texture of your saliva changed?
9. Are you experiencing any burning or soreness in your mouth or on your tongue?
10. Are you getting more cavities than previously experienced?

Assessment Procedures

Daily salivary production fluctuates, with a variance between 0.5 and 1.5 liters per day.² During sleep, the flow rate of saliva is almost zero. Resting or unstimulated saliva is produced primarily by the submandibular glands and has a typical flow rate of < 0.1 ml/min.³ The minor salivary glands, which number 800 to 1,000 and are located throughout the oral cavity, also contribute to the resting saliva.

Resting saliva may be clinically evaluated employing a simple chairside observational method. Retract the lower lip and gently blot the labial mucosa with a small piece of gauze. Droplets of saliva will begin to form at the orifices of the minor accessory glands. A normal salivary resting flow rate is observed between 30-60 seconds. If the time for droplets of saliva to occur is more than 60 seconds, the resting flow rate is below normal. If less than 30 seconds, the resting flow rate is high. 

Healthy unstimulated saliva is serous and clear in color. If the saliva appears stringy, frothy, bubbly, or very sticky in nature, this may signify that the water content or rate of production is low. Resting saliva may also be evaluated by instructing the patient to passively drool into a collection cup. 

The parotid glands are the major contributors to stimulated saliva, which may be clinically evaluated by having the patient chew on a wax pellet or piece of chewing gum, or suck on a lemon-flavored, sugar-free candy. The patient is instructed to expectorate into the collection funnel at regular intervals, and the sample is measured afterward.³

Treatment Efficacy

For a patient experiencing a mild degree of xerostomia, there are several lifestyle changes that will alleviate symptoms, making the condition more tolerable. The American Dental Association (ADA) suggests providing the following lifestyle recommendations for mild xerostomia⁴:

• sipping water or sugarless, caffeine-free drinks
• sucking on ice chips
• using lip lubricants frequently (every 2 hours recommended)
• chewing sugar-free gum or sucking on sugar-free candy
• avoiding salty or spicy foods or dry, hard-to-chew foods
• avoiding sticky, sugary foods
• avoiding irritants such as alcohol (including alcohol-containing mouth rinses), tobacco, and caffeine
• drinking fluids while eating carefully
• using a humidifier at night

While these lifestyle tips for managing mild xerostomia can be helpful, they often fail to alleviate the symptoms incurred by the moderately or severely xerostomic patient. The etiologic pathways contributing to moderate or severe xerostomia are primarily medications, autoimmune diseases, and head and neck radiation. For instance, the patient who is undergoing head and neck radiation will require a stronger regimen of therapeutic interventions to cope with the collateral damage placed upon the salivary glands than someone who is experiencing mild xerostomia. 

Ultimately, a xerostomic patient is concerned with effectiveness, sustained relief, and convenience in treatment. The dental professional is concerned with providing a confident recommendation that will be efficacious, supported by science, and that encourages patient compliance. There are many over-the-counter, water-based sprays and rinses designed for patients who suffer from mild to moderate xerostomia. However, their effectiveness may be limited, as a water-based product is short lasting with little sustainability in the oral cavity, requiring more frequent use. Saliva substitutes, often available in a rinse format for moderate-to-severe cases, provide relief for some patients, but sometimes require the mixing of powder and water. Lastly, systemic salivary substitutes in capsules or tablets may be recommended, although they present side effects such as nausea and excessive sweating, which may discourage patients from adopting this form of treatment.

A 2011 Cochrane Review stated that well designed, randomised controlled trials of topical interventions for dry mouth are required to provide evidence to guide clinical care.⁵ The review of 36 controlled trials found "no strong evidence" that any specific topical therapy (eg, sprays, lozenges, mouth rinses, gels, oils, chewing gum, or toothpastes) was effective for relieving the symptoms of dry mouth. Although chewing gum was shown to increase saliva production, there was no evidence that symptoms were improved. Oxygenated glycerol triester (OGT) saliva substitute spray did show evidence of effectiveness compared with a water based electrolyte spray. In addition, more research is needed on treatments such as a gel-releasing device worn in the mouth or a mouthcare system. The authors noted that "patient preference is an important consideration, together with consideration of the potential adverse effects."⁵ As more trials are published, more evidence on efficacy may become available.

Xerostomia can run the gamut from a minor inconvenience to a debilitating daily struggle. As dental professionals, dental hygienists have the unique opportunity to proactively identify, assess, and treat xerostomia.   

About the Author

Jo-Anne Jones, RDH
President
RDH Connection Inc
Springwater, Ontario

References

1. S Osailan, Pramanik R, Shirodaria S, et al. Investigating the relationship between hyposalivation and mucosal wetness. Oral Dis. 2011;17(1):109-114.

2. Iorgulescu G. Saliva between normal and pathological. Important factors in determining systemic and oral health. J Med Life. 2009;2(3):303-307.

3. Navazesh M, Kumar SK. Measuring salivary flow challenges and opportunities J Am Dent Assoc. 2008;139(Suppl):35S-40S.

4. American Dental Association. Oral Health Topics. Xerostomia. https://www.ada.org/en/member-center/oral-health-topics/xerostomia. Accessed February 10, 2020.

5. Furness S, Worthington HV, Bryan G, et al. Interventions for the management of dry mouth: topical therapies. Cochrane Database Syst Rev. 2011;(12):CD008934.