Improving oral health in nursing home residents: A cluster randomized trial of a shared oral care intervention

Objectives: To compare a designated shared oral care intervention in a group of public nursing home residents with a standard oral care programme, focusing on levels of oral plaque and oral inflammation. Methods: A cluster randomized field trial was undertaken in 14 Danish public nursing homes. There were 145 participants included in the intervention group and 98 in the control group. We undertook a six-month intervention based on the principle of situated interprofessional learning. The primary outcomes were plaque and inflammation levels measured with the mucosal plaque index (MPS); this was assessed at baseline, after three and six months (end of intervention), and at follow-up (six months postintervention). The odds ratios (OR) and 95% confidence intervals (CI) were estimated with ordinal regression. Results: Socio-demographic characteristics and oral health status at baseline were comparable between the two groups, with the exception of age: the intervention group were significantly younger than controls (median 82 vs 87 years). After three and six months, those receiving the shared oral care intervention had significantly lower plaque and inflammation than the control group. The adjusted ORs for a reduction in MPS were 11.8 (CI: 6.5-21.3) and 11.0 (CI: 5.8-20.9), respectively. At follow-up, plaque levels and oral inflammation had approached the pre-intervention level, with no remaining statistically significant group differences. Conclusions: The shared oral care intervention based on a situated learning perspective was effective in improving oral health among care home residents. However, after termination of the intervention, the effect quickly decreased. This confirms the challenges of achieving long-term improvement in oral health in nursing home residents. An implementation strategy focusing on achieving changes at both organizational and individual levels with persistent attention to oral health care seem required for long-term improvement.