Abstract: We included nine RCTs involving 3253 nursing home residents in this review; seven of these trials used cluster randomisation. The mean resident age ranged from 78 to 86 years across studies, and most participants were women (more than 66% in all studies). The proportion of residents with dental protheses ranged from 62% to 87%, and the proportion of edentulous residents ranged from 32% to 90% across studies. Eight studies compared educational interventions with information and practical components versus (optimised) usual care, while the ninth study compared educational interventions with information only versus usual care. All interventions included educational sessions on oral health for nursing staff (five trials) or for both staff and residents (four trials), and used more than one active component. Follow-up of included studies ranged from three months to five years. No study showed overall low risk of bias. Four studies had a high risk of bias, and the other five studies were at unclear risk of bias. None of the trials assessed our predefined primary outcomes 'oral health' and 'oral health-related quality of life'. All trials assessed our third primary outcome, 'dental or denture plaque'. Meta-analyses showed no evidence of a difference between interventions and usual care for dental plaque (mean difference -0.04, 95% confidence interval (CI) -0.26 to 0.17; six trials; 437 participants; low quality evidence) or denture plaque (standardised mean difference -0.60, 95% CI -1.25 to 0.05; five trials; 816 participants; low quality evidence). None of the studies assessed adverse events of the intervention. We found insufficient evidence to draw robust conclusions about the effects of oral health educational interventions for nursing home staff and residents. We did not find evidence of meaningful effects of educational interventions on any measure of residents' oral health; however, the quality of the available evidence is low. More adequately powered and high-quality studies using relevant outcome measures are needed.

Plain-language summary: We searched for relevant studies that had been conducted up until January 2016 and identified nine trials involving a total of 3253 nursing home residents. The average age of residents across the studies ranged from 78 to 86 years. In all of the studies most of the people taking part had dentures (between 62% and 87%). The trials evaluated a variety of approaches including educational programmes, skills training, and written information material. Topics included dental issues that were particularly relevant for older people such as care of dentures and covered dental and oral diseases, prevention of oral diseases, dental hygiene tools, and oral health care guidelines. The length of the trials ranged from three months to five years. We could not identify a clear benefit of training of nurses and/or residents on residents' dental health as assessed by dental and denture plaque. No study assessed oral health, oral health-related quality of life or adverse events. As education programmes were not fully described, results do not allow for clear conclusions about the effectiveness or potential harm of specific oral health education interventions in nursing homes. Overall, there was a low quality of information from the studies regarding all of the results. We conclude that there is a need for clinical trials to investigate the advantages and harms of oral health educational programmes in nursing homes.