The study focuses on professional oral care and staff education in intensive care units. The project was conducted at Semmelweis University and examined the impact of professional oral care on the health of critically ill patients. The study compared professional oral care with standard oral care while evaluating the effectiveness of ICU staff education in oral hygiene. The aim was to improve oral care outcomes in critically ill patients through specialized training of healthcare personnel. The project has been completed and its results contribute to improving oral hygiene care in critical conditions.