Background: Associations between nursing home residents' oral health status and quality of life, respiratory tract infections, and nutritional status have been reported. Educational interventions for nurses or residents, or both, focusing on knowledge and skills related to oral health management may have the potential to improve residents' oral health., Objectives: To assess the effects of oral health educational interventions for nursing home staff or residents, or both, to maintain or improve the oral health of nursing home residents., Search Methods: We searched the Cochrane Oral Health Trials Register (to 18 January 2016), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, 2015, Issue 12), MEDLINE Ovid (1946 to 18 January 2016), Embase Ovid (1980 to 18 January 2016), CINAHL EBSCO (1937 to 18 January 2016), and Web of Science Conference Proceedings (1990 to 18 January 2016). We searched ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform for ongoing trials to 18 January 2016. In addition, we searched reference lists of identified articles and contacted experts in the field. We placed no restrictions on language or date of publication when searching the electronic databases., Selection Criteria: Randomised controlled trials (RCTs) and cluster-RCTs comparing oral health educational programmes for nursing staff or residents, or both with usual care or any other oral healthcare intervention., Data Collection and Analysis: Two review authors independently screened articles retrieved from the searches for relevance, extracted data from included studies, assessed risk of bias for each included study, and evaluated the overall quality of the evidence. We retrieved data about the development and evaluation processes of complex interventions on the basis of the Criteria for Reporting the Development and Evaluation of Complex Interventions in healthcare: revised guideline (CReDECI 2). We contacted authors of relevant studies for additional information., Main Results: 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., Authors' Conclusions: 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.