Gum disease and tooth decay are the main reasons for tooth loss. Unless brushed away, plaque (a sticky film containing bacteria) can build up on the teeth, which can lead to gum inflammation. Plaque is also a key factor in the development of tooth decay. Interdental brushes are designed to clean between the teeth, to remove the plaque in harder to reach areas. They are small headed toothbrushes, available in a range of different widths to match the space between the teeth. They can be cone-shaped or cylindrical. Together with dental floss, interdental brushes are one of the most commonly recommended, advertised and available aids for cleaning between the teeth. But is there evidence that they really work to control tooth decay and reduce gum disease?
What was the research?
A systematic review of the evidence to find out whether interdental brushing in addition to toothbrushing, as compared to toothbrushing alone or toothbrushing and flossing, prevents and controls gum disease and tooth decay.
Who conducted the research?
The research was conducted by a team led by Tina Poklepovic from the University of Split, Croatia, on behalf of the Cochrane Oral Health Group. Helen V Worthington, Trevor M Johnson, Dario Sambunjak, Pauline Imai, Jan E Clarkson and Peter Tugwell were also on the team.
What evidence was included in the review?
Data was extracted from seven randomised controlled trials. A total of 354 people participated in the trials, and were randomly assigned to toothbrushing with interdental brushing, or toothbrushing with flossing or toothbrushing alone.
What did the evidence say?
There is some evidence that using interdental brushes plus toothbrushing is more beneficial than toothbrushing alone for the reduction of plaque after one month of use. There is also some evidence that using interdental brushes reduces gum inflammation by 52% when compared to flossing after one month, although there was no evidence that interdental brushing reduces plaque when compared to dental floss. None of the studies reported on tooth decay as they were not long enough in duration. Two studies reported some data on problems or harms during the study, including interdental brushes distorting or buckling, and soreness of gums due to dental floss.
How good was the evidence?
The evidence about the effectiveness of interdental brushing compared to brushing alone is based on only one study, and this was assessed at being at high risk of bias. Only one of the other seven studies, which compared flossing and toothbrushing with toothbrushing and interdental brushing was at low risk of bias. The evidence was generally therefore of low quality.
What are the implications for dentists and the general public?
The review found very low quality evidence that interdental brushing plus toothbrushing is more beneficial than toothbrushing alone for controlling gum disease and plaque after one month. There is also low-quality evidence that interdental brushing reduces gum disease when compared with flossing.
What should researchers look at in the future?
The length of the studies was relatively short, more long-term randomized controlled trials should be conducted to show the benefits or harms of using interdental brushes as part of a daily oral care routine. Accurate reporting about instructions given to the participants is important, for example, did the interdental brushing take place before, or after, the toothbrushing? Participants should have training and daily reminders, and future trials should report how well participants complied to the instructions in detail.
Poklepovic T, Worthington HV, Johnson TM, Sambunjak D, Imai P, Clarkson JE, Tugwell P. Interdental brushing for the prevention and control of periodontal diseases and dental caries in adults. Cochrane Database of Systematic Reviews 2013, Issue 12. Art. No.: CD009857. DOI: 10.1002/14651858.CD009857.pub2.