The evidence suggests that additional use of floss or interdental brushes compared to tooth brushing alone seems to reduce gingivitis or plaque, or both, and interdental brushes appear to be more effective than floss. The available evidence for cleaning sticks and oral irrigation aids is limited and uncertain. There are no serious adverse events and no evidence of a difference between study arms. The long-term significance of the findings is not clear and a few of the studies assessed pocket probing depth as a measure of periodontitis and none assessed interproximal caries. Caution should be taken while interpreting the findings due to heterogeneity among the included studies. Further studies are needed to address the present review question.
Overall summary Low risk of bias in the review
There was significant evidence of heterogeneity for the gingival index at 1 month, bleeding at 1 and 3 months and plaque at 1-month outcomes (tooth brushing plus floss versus tooth brushing alone group).
|A. Did the interpretation of findings address all of the concerns identified in Domains 1 to 4?||Probably yes|
|B. Was the relevance of identified studies to the review's research question appropriately considered?||Probably yes|
|C. Did the reviewers avoid emphasizing results on the basis of their statistical significance?||Probably yes|
|Risk of bias in the review||Low|
|Number of studies||35|
|Number of participants||3,929|
|Last search date||16 January 2019|
|Objective||To compare the effectiveness of interdental cleaning devices used at home, in addition to tooth brushing with tooth brushing alone, for preventing and controlling periodontal diseases, caries, and plaque and to compare different interdental cleaning devices with each other.|
|Population||Dentate participants irrespective of age, race, sex, socioeconomic status, geographical location, background exposure to fluoride, initial dental health status, setting, or time of intervention.
Studies were excluded if the majority of participants had any orthodontic appliances. Likewise, studies were excluded if participants were selected on the basis of special (general or oral) health conditions (for example, severely immunocompromised people), or if the majority of participants had severe periodontal disease.
|Interventions||Combination of tooth brushing and any home-use mechanical interdental cleaning device.
Studies using floss impregnated with active agents such as chlorhexidine or fluoride were included.
Studies were excluded if intervention or control groups receiving any additional active agent(s) (i.e. caries-preventive agents) as part of the study (e.g. chlorhexidine mouthwash, additional fluoride-based procedures, oral hygiene procedures, xylitol chewing gum), in addition to interdental cleaning procedures or tooth brushing and studies that compared two variations of the same type of interdental cleaning device were also excluded.
|Comparator||Tooth brushing alone, or with another mechanical interdental cleaning device.|
|Outcome||Primary outcomes: gingivitis (assessed by gingival indices and bleeding indices in separate analyses); periodontitis (assessed by clinical attachment loss and pocket probing depth); interproximal caries (assessed by (a) progression of caries into enamel or dentine, (b) change in decayed, missing and filled tooth surfaces (D(M)FS) index, (c) radiographic evidence), plaque (assessed by plaque scores or indices) and harms and adverse effects.
Secondary outcomes: halitosis, patient satisfaction and cost of the intervention.
|Study design||Randomised controlled trials (RCTs) including split-mouth design, crossover trials and cluster-randomised trials.|
The pooled analysis reported that gingival index at 1 month (standardised mean difference [SMD] -0.58, 95% confidence interval [CI] -1.12 to -0.04; 8 trials, 585 participants), 3 months (SMD -0.33, 95% CI -0.50 to -0.17; 4 trials, n = 570 participants) and 6 months (SMD -0.68, 95% CI -0.95 to -0.42; 4 trials, n = 564 participants) and plaque at 3 months (SMD -0.20, 95% CI -0.36 to -0.04; 5 trials, n = 594 participants) were decreased significantly with tooth brushing plus floss compared to tooth brushing alone. However, no significant difference was found between tooth brushing plus floss and tooth brushing alone in terms of bleeding at one month (mean difference [MD] -0.03, 95% CI -0.14 to 0.08; 2 trials, n = 158 participants), 3 months (MD -0.14, 95% CI -0.37 to 0.09; 2 trials, n = 240 participants), plaque at one month (SMD -0.42, 95% CI -0.85 to 0.02; seven trials, n = 542 participants) and six months (SMD -0.13, 95% CI -0.30 to 0.05; 3 trials, n = 487 participants).
The pooled analysis reported that gingival index at 1 month (SMD -0.48, 95% CI -0.89 to -0.06; 4 trials, 380 participants) decreased significantly with tooth brushing plus oral irrigation compared to tooth brushing alone. However, no significant difference was found between tooth brushing plus oral irrigation and tooth brushing alone in terms of 3 months (SMD -0.13, 95% CI -0.44 to 0.17; 2 trials, n = 163 participants), bleeding at one month (MD -0.00, 95% CI - 0.07 to 0.06; 2 trials, n = 126 participants), plaque at one month (SMD -0.16, 95% CI -0.41 to 0.10; 3 trials, n = 235 participants) and 3 months (SMD 0.06, -0.25 to 0.37; 2 trials, n = 163 participants).
The pooled analysis reported that gingival index at 1 month (SMD -0.40, 95% CI -0.70 to -0.11; 3 trials, n = 183 participants), bleeding at four to six weeks (MD -0.06, 95% CI -0.08 to -0.03; 6 trials, n = 234 participants) and at 3 months (MD -0.10, 95% CI -0.15 to -0.04; 2 trials, n = 106 participants), plaque at 1 month (SMD -0.47, 95% CI -0.84 to -0.11; 5 trials [parallel-group studies], n = 290 participants) decreased significantly with the interdental brush compared to floss. However, no significant difference was found between the interdental brush and floss in terms of plaque at three months (MD -0.12, 95% -0.33 to 0.10; 2 trials, n = 106 participants) and probing pocket depth scores (PPD) at 4 to 6 weeks (MD -0.06, 95% CI -0.27 to 0.16; 3 trials, n = 107 participants).
The pooled analysis reported no significant difference between rubber/elastomeric interdental cleaning stick and floss in terms of gingival index at 1 month to six weeks (SMD -0.22, 95% CI -0.69 to 0.24; 6 trials, n = 256 participants), the proportion of bleeding sites at one month (MD 0.03, 95% CI -0.08 to 0.03; 5 trials, n = 212 participants) and plaque at one month (SMD -0.08, 95% CI -0.46 to 0.29; 6 trials, n = 273 participants).
The research objective was clearly stated and appropriate inclusion criteria were defined. No restrictions were imposed based on study characteristics and sources of information.
|1.1 Did the review adhere to pre-defined objectives and eligibility criteria?||Probably yes|
|1.2 Were the eligibility criteria appropriate for the review question?||Probably yes|
|1.3 Were eligibility criteria unambiguous?||Probably yes|
|1.4 Were all restrictions in eligibility criteria based on study characteristics appropriate (e.g. date, sample size, study quality, outcomes measured)?||Probably yes|
|1.5 Were any restrictions in eligibility criteria based on sources of information appropriate (e.g. publication status or format, language, availability of data)?||Probably yes|
|Concerns regarding specification of study eligibility criteria||Low|
Cochrane Oral Health’s Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL; 2018, Issue 12) in the Cochrane Library; MEDLINE Ovid (1946 to 16 January 2019), EMBASE Ovid (1980 to 16 January 2019) and CINAHL EBSCO (1937 to 16 January 2019) databases were searched for relevant studies. US National Institutes of Health Trials Register (to 16 January 2019) and the WHO Clinical Trials Registry Platform were searched for ongoing studies. The reference lists of included studies and relevant systematic reviews were searched for further studies. The full search strategy was provided and found appropriate. Searches were not restricted to date, publication format or language. Two review authors were independently involved in the study selection process and disagreements between them were resolved by discussion with other authors.
|2.1 Did the search include an appropriate range of databases/electronic sources for published and unpublished reports?||Probably yes|
|2.2 Were methods additional to database searching used to identify relevant reports?||Probably yes|
|2.3 Were the terms and structure of the search strategy likely to retrieve as many eligible studies as possible?||Probably yes|
|2.4 Were restrictions based on date, publication format, or language appropriate?||Yes|
|2.5 Were efforts made to minimise error in selection of studies?||Yes|
|Concerns regarding methods used to identify and/or select studies||Low|
At least two review authors were independently involved in the data extraction process and disagreements between them were resolved by consensus. Sufficient study characteristics appear to have been extracted to allow interpretation of results. Relevant study results appear to have been extracted. The methodological quality of included studies was assessed using the Cochrane risk of bias assessment tool. Two review authors were independently involved in the risk of bias assessment.
|3.1 Were efforts made to minimise error in data collection?||Yes|
|3.2 Were sufficient study characteristics considered for both review authors and readers to be able to interpret the results?||Probably yes|
|3.3 Were all relevant study results collected for use in the synthesis?||Probably yes|
|3.4 Was risk of bias (or methodological quality) formally assessed using appropriate criteria?||Yes|
|3.5 Were efforts made to minimise error in risk of bias assessment?||Yes|
|Concerns regarding methods used to collect data and appraise studies||Low|
The synthesis appeared to include all eligible studies. The method of analysis was explained and appeared appropriate. There was significant evidence of heterogeneity for the gingival index at 1 month, bleeding at 1 and 3 months and plaque at 1-month outcomes (tooth brushing plus floss versus tooth brushing alone group). The authors did not explore heterogeneity through formal subgroup analyses due to there being a fewer number of studies that was prespecified (10). Sensitivity analysis was performed to test the robustness of findings. The quality of individual studies was considered in the synthesis.
|4.1 Did the synthesis include all studies that it should?||Probably yes|
|4.2 Were all pre-defined analyses reported or departures explained?||Probably yes|
|4.3 Was the synthesis appropriate given the degree of similarity in the research questions, study designs and outcomes across included studies?||Probably yes|
|4.4 Was between-study variation minimal or addressed in the synthesis?||Probably yes|
|4.5 Were the findings robust, e.g. as demonstrated through funnel plot or sensitivity analyses?||Probably yes|
|4.6 Were biases in primary studies minimal or addressed in the synthesis?||Probably yes|
|Concerns regarding synthesis and findings||Low|
Abstract - Background Dental caries (tooth decay) and periodontal diseases (gingivitis and periodontitis) affect the majority of people worldwide, and treatment costs place a significant burden on health services. Decay and gum disease can cause pain, eating and speaking difficulties, low self‐esteem, and even tooth loss and the need for surgery. As dental plaque is the primary cause, self‐administered daily mechanical disruption and removal of plaque is important for oral health. Toothbrushing can remove supragingival plaque on the facial and lingual/palatal surfaces, but special devices (such as floss, brushes, sticks, and irrigators) are often recommended to reach into the interdental area. Objectives To evaluate the effectiveness of interdental cleaning devices used at home, in addition to toothbrushing, compared with toothbrushing alone, for preventing and controlling periodontal diseases, caries, and plaque. A secondary objective was to compare different interdental cleaning devices with each other. Search methods Cochrane Oral Health’s Information Specialist searched: Cochrane Oral Health’s Trials Register (to 16 January 2019), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, 2018, Issue 12), MEDLINE Ovid (1946 to 16 January 2019), Embase Ovid (1980 to 16 January 2019) and CINAHL EBSCO (1937 to 16 January 2019). The US National Institutes of Health Trials Registry (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials. No restrictions were placed on the language or date of publication. Selection criteria Randomised controlled trials (RCTs) that compared toothbrushing and a home‐use interdental cleaning device versus toothbrushing alone or with another device (minimum duration four weeks). Data collection and analysis At least two review authors independently screened searches, selected studies, extracted data, assessed studies' risk of bias, and assessed evidence certainty as high, moderate, low or very low, according to GRADE. We extracted indices measured on interproximal surfaces, where possible. We conducted random‐effects meta‐analyses, using mean differences (MDs) or standardised mean differences (SMDs). Main results We included 35 RCTs (3929 randomised adult participants). Studies were at high risk of performance bias as blinding of participants was not possible. Only two studies were otherwise at low risk of bias. Many participants had a low level of baseline gingival inflammation. Studies evaluated the following devices plus toothbrushing versus toothbrushing: floss (15 trials), interdental brushes (2 trials), wooden cleaning sticks (2 trials), rubber/elastomeric cleaning sticks (2 trials), oral irrigators (5 trials). Four devices were compared with floss: interdental brushes (9 trials), wooden cleaning sticks (3 trials), rubber/elastomeric cleaning sticks (9 trials) and oral irrigators (2 trials). Another comparison was rubber/elastomeric cleaning sticks versus interdental brushes (3 trials). No trials assessed interproximal caries, and most did not assess periodontitis. Gingivitis was measured by indices (most commonly, Löe‐Silness, 0 to 3 scale) and by proportion of bleeding sites. Plaque was measured by indices, most often Quigley‐Hein (0 to 5). Primary objective: comparisons against toothbrushing alone Low‐certainty evidence suggested that flossing, in addition to toothbrushing, may reduce gingivitis (measured by gingival index (GI)) at one month (SMD ‐0.58, 95% confidence interval (CI) ‐1.12 to ‐0.04; 8 trials, 585 participants), three months or six months. The results for proportion of bleeding sites and plaque were inconsistent (very low‐certainty evidence). Very low‐certainty evidence suggested that using an interdental brush, plus toothbrushing, may reduce gingivitis (measured by GI) at one month (MD ‐0.53, 95% CI ‐0.83 to ‐0.23; 1 trial, 62 participants), though there was no clear difference in bleeding sites (MD ‐0.05, 95% CI ‐0.13 to .03; 1 trial, 31 participants). Low‐certainty evidence suggested interdental brushes may reduce plaque more than toothbrushing alone (SMD ‐1.07, 95% CI ‐1.51 to ‐0.63; 2 trials, 93 participants). Very low‐certainty evidence suggested that using wooden cleaning sticks, plus toothbrushing, may reduce bleeding sites at three months (MD ‐0.25, 95% CI ‐0.37 to ‐0.13; 1 trial, 24 participants), but not plaque (MD ‐0.03, 95% CI ‐0.13 to 0.07). Very low‐certainty evidence suggested that using rubber/elastomeric interdental cleaning sticks, plus toothbrushing, may reduce plaque at one month (MD ‐0.22, 95% CI ‐0.41 to ‐0.03), but this was not found for gingivitis (GI MD ‐0.01, 95% CI ‐0.19 to 0.21; 1 trial, 12 participants; bleeding MD 0.07, 95% CI ‐0.15 to 0.01; 1 trial, 30 participants). Very‐low certainty evidence suggested oral irrigators may reduce gingivitis measured by GI at one month (SMD ‐0.48, 95% CI ‐0.89 to ‐0.06; 4 trials, 380 participants), but not at three or six months. Low‐certainty evidence suggested that oral irrigators did not reduce bleeding sites at one month (MD ‐0.00, 95% CI ‐0.07 to 0.06; 2 trials, 126 participants) or three months, or plaque at one month (SMD ‐0.16, 95% CI ‐0.41 to 0.10; 3 trials, 235 participants), three months or six months, more than toothbrushing alone. Secondary objective: comparisons between devices Low‐certainty evidence suggested interdental brushes may reduce gingivitis more than floss at one and three months, but did not show a difference for periodontitis measured by probing pocket depth. Evidence for plaque was inconsistent. Low‐ to very low‐certainty evidence suggested oral irrigation may reduce gingivitis at one month compared to flossing, but very low‐certainty evidence did not suggest a difference between devices for plaque. Very low‐certainty evidence for interdental brushes or flossing versus interdental cleaning sticks did not demonstrate superiority of either intervention. Adverse events Studies that measured adverse events found no severe events caused by devices, and no evidence of differences between study groups in minor effects such as gingival irritation. Authors' conclusions Using floss or interdental brushes in addition to toothbrushing may reduce gingivitis or plaque, or both, more than toothbrushing alone. Interdental brushes may be more effective than floss. Available evidence for tooth cleaning sticks and oral irrigators is limited and inconsistent. Outcomes were mostly measured in the short term and participants in most studies had a low level of baseline gingival inflammation. Overall, the evidence was low to very low‐certainty, and the effect sizes observed may not be clinically important. Future trials should report participant periodontal status according to the new periodontal diseases classification, and last long enough to measure interproximal caries and periodontitis. Plain language summary Home use of devices for cleaning between the teeth (in addition to toothbrushing) to prevent and control gum diseases and tooth decay Review question How effective are home‐use interdental cleaning devices, plus toothbrushing, compared with toothbrushing only or use of another device, for preventing and controlling periodontal (gum) diseases (gingivitis and periodontitis), tooth decay (dental caries) and plaque? Background Tooth decay and gum diseases affect most people. They can cause pain, difficulties with eating and speaking, low self‐esteem, and, in extreme cases, may lead to tooth loss and the need for surgery. The cost to health services of treating these diseases is very high. As dental plaque (a layer of bacteria in an organic matrix that forms on the teeth) is the root cause, it is important to remove plaque from teeth on a regular basis. While many people routinely brush their teeth to remove plaque up to the gum line, it is difficult for toothbrushes to reach into areas between teeth ('interdental'), so interdental cleaning is often recommended as an extra step in personal oral hygi ne routines. Different tools can be used to clean interdentally, such as dental floss, interdental brushes, tooth cleaning sticks, and water pressure devices known as oral irrigators. Study characteristics Review authors working with Cochrane Oral Health searched for studies up to 16 January 2019. We identified 35 studies (3929 adult participants). Participants knew that they were in an experiment, which might have affected their teeth cleaning or eating behaviour. Some studies had other problems that might make their findings less reliable, such as people dropping out of the study or not using the assigned device. Studies evaluated the following devices plus toothbrushing compared to toothbrushing only: floss (15 studies), interdental brushes (2 studies), wooden cleaning sticks (2 studies), rubber/elastomeric cleaning sticks (2 studies) and oral irrigators (5 studies). Four devices were compared with floss: interdental brushes (9 studies), wooden cleaning sticks (3 studies), rubber/elastomeric cleaning sticks (9 studies), oral irrigators (2 studies). Three studies compared rubber/elastomeric cleaning sticks with interdental brushes. No studies evaluated decay, and few evaluated severe gum disease. Outcomes were measured at short (one month to six weeks) and medium term (three and six months). Key results We found that using floss, in addition to toothbrushing, may reduce gingivitis in the short and medium term. It is unclear if it reduces plaque. Using an interdental brush, in addition to a toothbrush, may reduce gingivitis and plaque in the short term. Using wooden tooth cleaning sticks may be better than toothbrushing only for reducing gingivitis (measured by bleeding sites) but not plaque in the medium term (only 24 participants). Using a tooth cleaning stick made of rubber or an elastomer may be better than toothbrushing only for reducing plaque but not gingivitis in the short term (only 30 participants). Toothbrushing plus oral irrigation (water pressure) may reduce gingivitis in the short term, but there was no evidence for this in the medium term. There was no evidence of a difference in plaque. Interdental brushes may be better than flossing for gingivitis at one and three months. The evidence for plaque is inconsistent. There was no evidence of a difference between the devices for periodontitis measured by probing pocket depth. There is some evidence that oral irrigation may be better than flossing for reducing gingivitis (but not plaque) in the short term. The available evidence for interdental cleaning sticks did not show them to be better or worse than floss or interdental brushes for controlling gingivitis or plaque. The studies that measured 'adverse events' found no serious effects and no evidence of differences between study groups in minor effects such as gum irritation. Certainty of the evidence The evidence is low to very low‐certainty. The effects observed may not be clinically important. Studies measured outcomes mostly in the short term and many participants had a low level of gum disease at the beginning of the studies. Future research Future studies should use the new periodontal diseases classification to describe the gum health of participants, and they should last long enough to measure periodontitis and tooth decay.