Tooth decay is a common disease affecting up to 90% of children and most adults worldwide. It impacts on quality of life and can be the reason for thousands of children needing dental treatment under general anaesthetic in hospital. However, it can easily be prevented and treated by good oral health habits such as brushing teeth regularly with toothpaste that contains fluoride and cutting down on sugary food and drinks. If left undisturbed, the unhelpful bacteria in the mouth – which cause decay – multiply and stick to the surfaces of teeth producing a sticky film. Then, when sugar is eaten or drank, the bad bacteria in the film are able to make acid resulting in tooth decay. Xylitol is a natural sweetener, which is equally as sweet as normal sugar (sucrose). As well as providing an alternative to sugar, it has other properties that are thought to help prevent tooth decay, such as increasing the production of saliva and reducing the growth of bad bacteria in the mouth so that less acid is produced. In humans, xylitol is known to cause possible side effects such as bloating, wind and diarrhoea.
What was the research?
A systematic review of the evidence to assess the effects of different xylitol-containing products for the prevention of dental caries in children and adults.
Who conducted the research?
The research was conducted by a team led by Philip Riley, on behalf of the Cochrane Oral Health Group. Deborah Moore, Mohammed O. Sharif, Farooq Ahmed and Helen Worthington were also on the team.
What evidence was included in the review?
Data was extracted from 10 randomised controlled trials. A total of 5,903 people participated in the trials, and were randomly assigned to receive xylitol products or a placebo or no treatment. The amount of tooth decay was compared. One study included adults, the others included children aged from 1 month to 13 years. The products tested were the kind that are held in the mouth and sucked (lozenges, sucking tablets and sweets) or slowly released through a dummy/pacifier, as well as toothpastes, syrups, and wipes.
What did the evidence say?
There is some evidence to suggest that using a fluoride toothpaste containing xylitol may reduce tooth decay in the permanent teeth of children by 13% over a 3 year period when compared to a fluoride-only toothpaste. Over this period, there were no side effects reported by the children. The remaining evidence we found did not allow us to conclude whether or not any other xylitol-containing products can prevent tooth decay in infants, older children, or adults.
How good was the evidence?
The evidence presented is of low to very low quality due to the small amount of available studies, uncertain results, and issues with the way in which they were conducted.
What are the implications for dentists and the general public?
There was some low quality evidence to suggest that fluoride toothpaste containing xylitol may be more effective than fluoride only toothpaste for preventing tooth decay in children’s teeth, and that there are no adverse effects from these toothpastes. The remaining evidence is of low to very low quality, and did not allow the researchers to make a decision as to whether other xylitol products can prevent tooth decay.
What should researchers look at in the future?
More randomized controlled trials on this topic are needed. The authors recommend that a range of vehicles used to deliver xylitol are tested, and at a range of doses,
Riley P, Moore D, Ahmed F, Sharif MO, Worthington HV. Xylitol-containing products for preventing dental caries in children and adults. Cochrane Database of Systematic Reviews 2015, Issue 3. Art. No.: CD010743. DOI: 10.1002/14651858.CD010743.pub2.