Abstract Ventilator-associated pneumonia (VAP) is the most common nosocomial infection reported among mechanically ventilated patients. VAP is an emerging concept and remains a significant clinical problem for critically ill patients. Although VAP is often preventable, its effects on morbidity, mortality, length of hospital stay, and cost are enormous. VAP is not a new diagnosis, but education and research on the prevention of this serious problem are still continuing. Oropharyngeal colonization is the main risk factor for the development of VAP. Oral health can be compromised by critical illness and mechanical ventilation. It can also be influenced by nursing attentions. Therefore, education and focus on suitable oral care strategies are necessary. Moreover, nursing research to define the best process for all patients in ICU is needed. Whether nursing actions decrease VAP rates remains an empirical question that requires more research since no valid and reliable survey could be found in the literature for oral care practices on orally intubated critically ill patients. An oral care survey for orally intubated patients is hence essential to determine the best existing practices. Many studies have thus attempted to determine the effects of this intervention on the incidence of VAP. The present study aimed to review the literature focusing on oral hygiene in prevention of VAP.