Oral Health Improvement for Nursing Home Residents Through Delegated Remotivation and Reinstruction - a Cluster-randomized Controlled Trial

Oral health and oral-health-associated quality-of-life (OHrQL) of residents in German nursing homes are poor. The investigators will develop an evidence-based catalogue of interventions applicable and sustainable ("Oral Health Tool Box"). Based on this, care-accompanying reinstruction and remotivation of nursing staff by dental assistants (DA) will be provided. The investigators hypothesize such complex intervention to significantly improve OHrQL, and daily oral hygiene/care behaviour and its cost-effectiveness.

Methods and analysis: Based on the findings of a rapid systematic review, possible intervention components will be systematized and assessed for their effectiveness. Mixed methods will be used to identify barriers and enablers of oral hygiene and care in German long-term residential care (LRC), and these will be linked with the intervention components using the Theoretical Domains Framework and the Behavior Change Wheel, the result being an "Oral Health Tool Box". A two-arm cluster, randomized-controlled-trial (ratio of 1:1 via block randomization) will be performed in nursing homes in Rhineland-Palatinate, Germany, including residents with moderate to severe care dependency. Each nursing home represents a cluster. Based on a feasibility study, considering clustering and possible attrition, the investigators aim at recruiting 618 residents of 18 cluster. In the intervention group, dentists will identify the specific problems of each resident, and assign one or more intervention components from the box. During follow-up, nursing staff will be reinstructed and remotivated by dental assistants in how to deliver the intervention components in individual intervals. In the control group residents will receive care as usual. The primary outcome, OHrQL, will be measured using the German version of the General Oral Health Assessment Index (GOHAI). Secondary outcomes include pain condition, general health-related quality-of-life, caries increment, oral/prothetic hygiene and gingival status, incidence of dental emergencies and hospitalizations, and cost-utility/effectiveness. The endpoints will be measured at baseline and after 12 months. For the primary outcome, a mixed-linear model will be used within an intention-to-treat analysis. A process evaluation using mixed methods will be conducted alongside the trial.

Due to the pandemic, the number of cases could not be reached despite outstanding commitment in recruitment. An application was made to the funding agency to adapt the project plan.