Introduction:
Non-ventilator hospital-acquired pneumonia (NV-HAP) is an important patient-safety problem in acute care. Oral care is increasingly recognized as a preventive nursing intervention, but implementation in routine practice remains insufficiently understood.

Methods:
A systematic review with narrative synthesis was conducted in PubMed, EBSCOhost, and Scopus, supplemented by Google Scholar, citation tracking, and manual reference screening. Eligible studies involved hospitalized adults, nurse-led or nursing assistant-delivered oral care, and outcomes related to hospital-acquired pneumonia or NV-HAP. Study selection followed PRISMA 2020. Methodological quality was assessed using design-appropriate Joanna Briggs Institute (JBI) criteria.

Results:
Fifteen studies and implementation reports were included. Four recurring strategies were identified: staff education, protocolized oral care, documentation and monitoring systems, and multicomponent prevention bundles. These approaches generally improved staff knowledge, adherence, oral care frequency, and documentation. Clinical outcomes were less consistent, although several controlled and quasi-experimental studies reported reductions in NV-HAP. Most studies had moderate-to-high risk-of-bias concerns because of nonrandomized designs, uncontrolled before-after methods, and the inclusion of oral care within broader prevention programs.

Conclusions:
Nurse-led oral care is more likely to succeed when supported by education, standardized protocols, adequate supplies, documentation, leadership, and monitoring. However, the evidence remains heterogeneous and methodologically limited, so conclusions should be interpreted cautiously and generalized only to comparable acute care settings.