A process evaluation of a complex oral health intervention tested across German nursing homes revealed significant implementation inconsistencies, with individualized oral care recommendations fully carried out for only about half of observed participants. Despite an overall positive perception of the concept among participating groups, researchers found that daily execution varied substantially across facilities.
The investigation was nested within the cluster-randomised controlled MundZaRR trial, which evaluated an intervention designed to improve the frequently poor oral health of residents across 18 nursing homes involving 271 participants. The accompanying process evaluation followed international guidelines to explore the experiences of multiple target groups and gather comprehensive insights into how the intervention was delivered in practice.
Data collection took place in Germany between July 2022 and October 2023 and incorporated both qualitative and quantitative approaches. The researchers conducted 23 individual, semi-structured interviews and three focus groups with dentists, dental assistants, nursing home managers, nursing staff, and resident council members, complemented by 20 participatory observations, written surveys, structured protocols, and document analysis, with quantitative data analysed descriptively and qualitative material analysed through content analysis.
As part of the intervention, three educational training courses lasting approximately nine hours were conducted for dentists and dental assistants, running largely as planned and receiving positive evaluations. However, one out of nine nursing homes in the intervention arm could not implement the program at all because of staff and time shortages, while the remaining facilities showed considerable variation in implementation fidelity and in the degree of cooperation between dental assistants and nursing staff.
Direct observations indicated that more specific dental hygiene measures, such as interdental cleaning, were only rarely carried out for residents. Key barriers to implementation included shortages of staff and time, a lack of interest or engagement among nursing personnel, and resident-specific factors such as uncooperative behaviour and poor general health, while recruitment difficulties related to the COVID-19 pandemic did not predominantly disrupt the subsequent course of the trial.
Reflecting on these findings, the study authors concluded that despite the overall positive reception of the intervention concept by the various target groups, substantial inconsistencies remained in how the program was delivered across the nursing homes assigned to the intervention group. They emphasized that the structural and individual barriers identified across the participating facilities provide critical indications to guide the future development and practical implementation of comparable oral health initiatives in nursing home settings.
The underlying trial was formally registered with ClinicalTrials.gov under the registration number NCT04140929 on October 24, 2019.
Subject of Research: Implementation of oral health interventions in nursing homes
Article Title: Process evaluation of a complex intervention to improve the oral health of nursing home residents (MundZaRR): a multimethod study
Article References: Wobst, L.-M., Meyer, G., Habig, S., Gabelmann, S., Hertrampf, K., Gaßmann, G., Schwendicke, F., Schlattmann, P., Orawa, H., & Abraham, J. (2026). Process evaluation of a complex intervention to improve the oral health of nursing home residents (MundZaRR): a multimethod study. BMC Geriatrics. https://doi.org/10.1186/s12877-026-08607-z
Image Credits: AI Generated
DOI: 10.1186/s12877-026-08607-z
Keywords: oral health, nursing homes, process evaluation, geriatric care, MundZaRR trial, implementation fidelity, health services research, Process, evaluation, complex, intervention, improve
