Abstract
Non‐drug treatments for dry mouth symptoms
Review question
This review, carried out by authors of the Cochrane Oral Health Group, has been produced to assess the effects of non‐drug treatments used to stimulate saliva production for the relief of dry mouth (xerostomia) symptoms.
Background
Dry mouth is a common problem with an estimated incidence of between 10% and 26% in men and between 10% and 33% in women, which may or may not be due to reduced saliva secretion. Common causes of dry mouth include the side effects of many commonly prescribed medications, diseases (such as Sjögren's syndrome where the immune system destroys tissues in the glands which produce saliva) and radiotherapy treatments for head and neck cancers.
Saliva moistens the skin in the mouth and helps to maintain oral health. The presence of saliva facilitates speech, acts to wash away food residue from around the teeth, neutralises potentially damaging food and bacterial acids, enhances a person's ability to taste the food, and generally lubricates the mouth. Saliva also acts to soften food, making it easier to chew and swallow. Enzymes in saliva start the digestion of starch and fats, and other substances in saliva, such as epidermal growth factors, promote tissue growth, differentiation and wound healing. The antibacterial, antifungal and antiviral agents in saliva balance the oral flora and help to prevent oral infections, while the minerals in saliva help to maintain tooth enamel.
Non‐drug treatments such as acupuncture, mild electrical stimulation, lasers, tooth brushing and other stimulation techniques are used to improve dry mouth symptoms.
Study characteristics
The evidence on which this review is based was up‐to‐date as of 16 April 2013.
Nine studies were included in this review. A total of 366 adult participants took part in these trials, with an average of 40 participants per trial, and an age range from 12 to 77 years. The causes of dry mouth were radiotherapy for oral cancers in four trials, Sjögren's syndrome in three trials, medication‐related in one trial, and in the remaining trial participants had a range of causes of dry mouth.
The included studies were divided into three groups, according the interventions evaluated.
1. Five small studies with a total 153 participants evaluated acupuncture.
2. Three studies evaluated electrostimulation devices.
3. One study evaluated a power toothbrush.
Key results
The five studies evaluating the effects of acupuncture in people who had dry mouth were generally of poor quality. There was no evidence of a difference in dry mouth symptoms, but there was some evidence of a small increase in saliva production which persisted for a year after the end of the acupuncture treatment. There may not have been enough people included in the trials to show a difference in dry mouth, or it may have been that both the real acupuncture and the 'placebo' acupuncture had some beneficial effect. Acupuncture was associated with more adverse effects (tiny bruises and tiredness which were mild and temporary).
The studies evaluating the effects of electrostimulation devices were poorly conducted and reported, and provided insufficient evidence to determine the effects of these devices on either dry mouth or saliva production.
The single small study of a powered versus a manual toothbrush also found no difference for either dry mouth or saliva production.
None of the included studies reported the outcomes of duration of effectiveness, quality of life, patient satisfaction, or oral health assessment.
Quality of the evidence
These studies were generally of poor quality (low and very low).