Periodontal (gum) disease and dental caries (tooth decay) are the most common causes of tooth loss; dental plaque plays a major role in the development of these diseases. Effective oral hygiene involves removing dental plaque, for example, by regular toothbrushing. People with intellectual disabilities (ID) can have poor oral hygiene and oral health outcomes.
To assess the effects (benefits and harms) of oral hygiene interventions, specifically the mechanical removal of plaque, for people with intellectual disabilities (ID).
Cochrane Oral Health’s Information Specialist searched the following databases to 4 February 2019: Cochrane Oral Health’s Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL; Cochrane Register of Studies), MEDLINE Ovid, Embase Ovid and PsycINFO Ovid. ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials. The Embase search was restricted by date due to the Cochrane Centralised Search Project, which makes available clinical trials indexed in Embase through CENTRAL. We handsearched specialist conference abstracts from the International Association of Disability and Oral Health (2006 to 2016).
We included randomised controlled trials (RCTs) and some types of non‐randomised studies (NRS) (non‐RCTs, controlled before‐after studies, interrupted time series studies and repeated measures studies) that evaluated oral hygiene interventions targeted at people with ID or their carers, or both. We used the definition of ID in the International Statistical Classification of Diseases and Related Health Problems, 10th revision (ICD‐10). We defined oral hygiene as the mechanical removal of plaque. We excluded studies that evaluated chemical removal of plaque, or mechanical and chemical removal of plaque combined.
Data collection and analysis
At least two review authors independently screened search records, identified relevant studies, extracted data, assessed risk of bias and judged the certainty of the evidence according to GRADE criteria. We contacted study authors for additional information if required. We reported RCTs and NRSs separately.
We included 19 RCTs and 15 NRSs involving 1795 adults and children with ID and 354 carers. Interventions evaluated were: special manual toothbrushes, electric toothbrushes, oral hygiene training, scheduled dental visits plus supervised toothbrushing, discussion of clinical photographs showing plaque, varied frequency of toothbrushing, plaque‐disclosing agents and individualised care plans. We categorised results as short (six weeks or less), medium (between six weeks and 12 months) and long term (more than 12 months).
Most studies were small; all were at overall high or unclear risk of bias. None of the studies reported quality of life or dental caries. We present below the evidence available from RCTs (or NRS if the comparison had no RCTs) for gingival health (inflammation and plaque) and adverse effects, as well as knowledge and behaviour outcomes for the training studies.
Very low‐certainty evidence suggested a special manual toothbrush (the Superbrush) reduced gingival inflammation (GI), and possibly plaque, more than a conventional toothbrush in the medium term (GI: mean difference (MD) –12.40, 95% CI –24.31 to –0.49; plaque: MD –0.44, 95% CI –0.93 to 0.05; 1 RCT, 18 participants); brushing was carried out by the carers. In the short term, neither toothbrush showed superiority (GI: MD –0.10, 95% CI –0.77 to 0.57; plaque: MD 0.20, 95% CI –0.45 to 0.85; 1 RCT, 25 participants; low‐ to very low‐certainty evidence).
Moderate‐ and low‐certainty evidence found no difference between electric and manual toothbrushes for reducing GI or plaque, respectively, in the medium term (GI: MD 0.02, 95% CI –0.06 to 0.09; plaque: standardised mean difference 0.29, 95% CI –0.07 to 0.65; 2 RCTs, 120 participants). Short‐term findings were inconsistent (4 RCTs; low‐ to very low‐certainty evidence).
Low‐certainty evidence suggested training carers in oral hygiene care had no detectable effect on levels of GI or plaque in the medium term (GI: MD –0.09, 95% CI –0.63 to 0.45; plaque: MD –0.07, 95% CI –0.26 to 0.13; 2 RCTs, 99 participants). Low‐certainty evidence suggested oral hygiene knowledge of carers was better in the medium term after training (MD 0.69, 95% CI 0.31 to 1.06; 2 RCTs, 189 participants); this was not found in the short term, and results for changes in behaviour, attitude and self‐efficacy were mixed.
One RCT (10 participants) found that training people with ID in oral hygiene care reduced plaque but not GI in the short term (GI: MD –0.28, 95% CI –0.90 to 0.34; plaque: MD –0.47, 95% CI –0.92 to –0.02; very low‐certainty evidence).
One RCT (304 participants) found that scheduled dental recall visits (at 1‐, 3‐ or 6‐month intervals) plus supervised daily toothbrushing were more likely than usual care to reduce GI (pocketing but not bleeding) and plaque in the long term (low‐certainty evidence).
One RCT (29 participants) found that motivating people with ID about oral hygiene by discussing photographs of their teeth with plaque highlighted by a plaque‐disclosing agent, did not reduce plaque in the medium term (very low‐certainty evidence).
One RCT (80 participants) found daily toothbrushing by dental students was more effective for reducing plaque in people with ID than once‐ or twice‐weekly toothbrushing in the short term (low‐certainty evidence).
A benefit to gingival health was found by one NRS that evaluated toothpaste with a plaque‐disclosing agent and one that evaluated individualised oral care plans (very low‐certainty evidence).
Most studies did not report adverse effects; of those that did, only one study considered them as a formal outcome. Some studies reported participant difficulties using the electric or special manual toothbrushes.
Although some oral hygiene interventions for people with ID show benefits, the clinical importance of these benefits is unclear. The evidence is mainly low or very low certainty. Moderate‐certainty evidence was available for only one finding: electric and manual toothbrushes were similarly effective for reducing gingival inflammation in people with ID in the medium term. Larger, higher‐quality RCTs are recommended to endorse or refute the findings of this review. In the meantime, oral hygiene care and advice should be based on professional expertise and the needs and preferences of the individual with ID and their carers.
Plain language summary
Oral hygiene programmes for people with intellectual disabilities
How effective are oral hygiene programmes for people with intellectual disabilities?
The removal of dental plaque by daily toothbrushing plays a major role in preventing tooth decay and gum disease, the two main causes of tooth loss. Toothbrushing is a skill that can be difficult for people with ID; they may require help and people who care for them may need training in how to help them.
We searched for studies up to 4 February 2019. This review included 34 studies that involved 1795 people with ID and 354 carers. Nineteen studies randomly allocated participants to two or more groups (i.e. randomised controlled trials (RCTs), and 15 were non‐randomised studies (NRS).
The studies assessed different ways to improve the oral hygiene of people with ID: special manual toothbrushes; electric toothbrushes; oral hygiene training for carers; oral hygiene training for people with ID; varying the scheduled intervals between dental visits and supervising toothbrushing; using discussion of clinical photographs as a motivator; varying how frequently the teeth of people with ID were brushed; using a plaque‐disclosing agent and using individualised oral care plans.
The studies evaluated gingival inflammation (red and swollen gums) and plaque. Some studies evaluated carer knowledge, behaviour, attitude and self‐efficacy (belief in their competence) in terms of oral hygiene, as well as the oral hygiene behaviour and skills of people with ID. Tooth decay and quality of life were not measured. We grouped the studies according to when the outcomes were measured: short term (six weeks or less), medium term (between six weeks and 12 months) and long term (more than 12 months).
A special manual toothbrush (the Superbrush), used by carers, may be better at reducing levels of gingival inflammation and possibly plaque in people with ID than an ordinary manual toothbrush in the medium term, though this was not seen in the short term.
We found no difference between electric and manual toothbrushes used by people with ID or their carers in terms of gingival inflammation or plaque in the medium term, and the short‐term results were unclear.
Training carers to brush the teeth of people with ID may have improved carers’ oral hygiene knowledge in the medium term.
Training people with ID to brush their own teeth may have reduced the amount of plaque on their teeth in the short term.
Regularly scheduled dental recall visits and carers supervising toothbrushing between visits may have been more likely than usual care to reduce gingival inflammation and plaque in the long term.
Discussing clinical photographs of plaque on participants’ teeth shown up by a disclosing agent, to motivate them to better toothbrushing did not seem to reduce plaque.
Daily toothbrushing by a dental student may be more effective for reducing plaque levels in the short term than once or twice weekly professional toothbrushing.
Toothpaste with a plaque‐disclosing agent and individualised oral care plans were each evaluated in one nonrandomised study that suggested they may be beneficial.
Only one study set out to formally measure negative side effects; however, most studies commented that there were none. Some studies found that some people had difficulties with the electric or special manual toothbrushes.
Certainty of the evidence
Although some oral hygiene interventions for people with ID show scientific evidence of benefits, what these benefits actually mean for an individual’s oral hygiene or oral health is unclear. The certainty of the evidence is mainly low or very low so future research may change our findings. Moderate‐certainty evidence is available for only one finding: electric and manual toothbrushes are probably similarly effective for reducing gingival inflammation in people with ID in the medium term. More and better research is needed to fully evaluate interventions that show promise for improving the oral hygiene of people with ID, and to confirm which interventions are ineffective. In the meantime, changes to current habits based on this review should be made cautiously, and decisions about oral hygiene care should be based on professional expertise and the needs and preferences of people with ID and their carers.