Although an adequate saliva secretion plays a key role in maintaining good oral health, many patients, perhaps through a long-standing acceptance of the discomfort, will fail to mention they are suffering from what is commonly called a dry mouth, or xerostomia.
In most healthy adults the volume of saliva production varies between two and six cupfuls per day, and xerostomia is identified when this drops to below one cupful. Saliva is responsible for hygiene and lubrication throughout the oral cavity, where it helps to control harmful bacteria, regulates pH levels, eliminates food particles and re-mineralises and maintains the integrity of the oral mucosa.
Saliva is produced by the parotid, submaxillary, sublingual and other, smaller mucous glands within the mouth. Analysis reveals a complex, serous fluid which contains two major types of protein: the digestive enzyme ptyalin and a mucous secretion which carries the lubricating aid mucin; significant concentrations of potassium and bicarbonate ions are present, and smaller amounts of sodium and chloride ions. Other constituents include the antimicrobial agents thiocyanate, lysozyme, immunoglobulins, lactoferrin and transferrin. The complexity of saliva’s composition indicates a multiplicity of functions, and a restricted salivary flow is potentially damaging to the patient’s overall health, even beyond the oral area.
Within the mouth the lack of an adequate saliva flow increases the likelihood of periodontal disease, caries, soft tissue inflammation and fissuring of the lips (chelitis). Other common consequences are inflammation or ulcers of the tongue and buccal mucosa, oral candidiasis, salivary gland infection (sialadenitis), and cracking and fissuring of the oral mucosa. Patients often complain of excessive thirst, especially at night, a burning sensation of the tongue, reduced taste sensations, a sore throat, halitosis and dry nasal passages. Further symptoms include difficulties with mastication, especially dry foodstuffs, swallowing, and sometimes speaking. Denture wearers may experience problems with retention, sores and the tongue attaching to the palate.
Xerostomia occurs with varying degrees of severity, and in more extreme cases will have significant adverse effects on the patient’s quality of life. Dentists who suspect xerostomia should ask the patient the following questions, with a single affirmative response indicating that the condition is present:
λ Does your mouth feel dry when eating?
λ Do you have difficulty swallowing?
λ Do you have to sip liquids in order to swallow dry food?
λ Does your mouth feel dry most of the time?
The most common cause of xerostomia are medications for some psychiatric conditions, and for pain relief, colds, or allergy control, and while varying or reducing the dosage will alleviate the symptoms, for many patients this will not be possible. Xerostomia is also a recognised and continuing prodrome of many specific and systemic diseases, including diabetes, rheumatoid arthritis and high blood pressure, and is frequently observed as a side effect of radiation and chemotherapy treatment for cancer of the head and neck. The surgical removal of salivary glands during cancer treatment is another obvious cause.
Another very common cause of xerostomia is Sjögren’s syndrome, an autoimmune disease which impairs the function of the salivary and lachrymal glands. Current estimates suggest that about half a million people in the UK, 90 per cent of them women, have the condition, which is now known to be hereditary to some degree and can occur at any age, although most often develops between the ages of 40 and 60.
In most cases addressing the cause(s) of xerostomia will be beyond the dentist’s remit, but steps can still be taken to reduce its impact and offer the patient some relief from the discomfort of a dry mouth. These steps comprise the prevention of dental caries, physically reducing the symptoms, and attempting to increase the flow of saliva.
All patients should be educated to undertake a regular routine of twice daily brushing and interdental teeth cleaning, with dry mouth sufferers advised to use a super-soft toothbrush to reduce the risk of trauma to periodontal tissues made more vulnerable by the absence of sufficient saliva. A warning should be given against the use of products containing sodium lauryl sulphate, which has the potential to further aggravate already sensitive tissue. A wide spectrum of adjunctive treatments is also available to dentists to improve oral lubrication, in the form of mouthwashes, oral sprays, saliva substitute gel, gum, capsules and pastilles.
A study involving Xerostom branded products from Curaprox showed that using these products daily over a period of seven days induced a 200 per cent increase in unstimulated saliva flow rates. These products contain selected pH neutral ingredients (olive oil, betaine and xylitol) to address all three of the issues which come within the competence of the dentist: protection from caries, reducing the irritation often associated with a dry mouth, and promoting an increased flow of saliva.
Patients suffering with xerostomia should be advised to examine their mouths everyday looking for red, white or dark patches, ulcers or signs of tooth decay. In the event they notice something new or unusual, they should immediately contact their dentist.
Saliva production averages 1.5l to 1.8l per person, per day (2.6 to three pints) and is essential for continued wellbeing. It is also important in terms of pain relief provided by opiorphins, and without it, a person will experience reduced, metallic, taste sensations. Additionally, having a dry mouth is often the cause of failure with regards to dental restorations. It can sometimes be taken for granted, but saliva plays an important role in the quality of everyday life. How many people with a dry mouth enjoy kissing?
References available on request.
For more information call 01480 862080, email clare@curaprox.co.uk or visit www.curaprox.co.uk