Oral hygiene interventions for people with intellectual disabilities

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.

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.